Host cities:
| Athlete | Nation(s) | Sport(s) | Role(s) | Era | Notes |
|---|---|---|---|---|---|
| Tom McKean | ATH | Olympics | 1988—1992 | 1–1–0 1986 Stuttgart silver: 800 m; 1990 Split gold: 800 m | |
| Jenny Meadows | ATH | Olympics | 2008 | 0–1–0 2010 Barcelona silver: 800 m | |
| Alf Meakin | ATH | Olympics | 1964 | 0–0–1 1962 Beograd bronze: 4×100 m relay | |
| Adel Mechaal | ATH | Olympics | 2016—2024 | 0–1–0 2016 Amsterdam silver: 5000 m | |
| Lajos Mecser | ATH | Olympics | 1964—1968 | 0–1–0 1966 Budapest silver: 10000 m | |
| Stefano Mei | ATH | Olympics | 1984—1988 | 1–1–1 1986 Stuttgart gold: 10000 m, silver: 5000 m; 1990 Split bronze: 10000 m | |
| Petra Meier-Felke | ATH | Olympics | 1988—1992 | 0–1–1 1986 Stuttgart silver: javelin throw (competed as Petra Felke for East Germany); 1990 Split bronze: javelin throw (competed as Petra Felke for East Germany) | |
| Walter Meier | ATH | Olympics | 1956—1960 | 0–0–1 1958 Stockholm bronze: decathlon | |
| Heike Meißner | ATH | Olympics | 1992—2000 | 0–1–1 1994 Helsinki bronze: 4×400 m relay; 2002 München silver: 400 m hurdles | |
| Mahiedine Mekhissi-Benabbad | ATH | Olympics | 2008—2016 | 5–0–0 2010 Barcelona gold: 3000 m steeplechase; 2012 Helsinki gold: 3000 m steeplechase; 2014 Zürich gold: 1500 m; 2016 Amsterdam gold: 3000 m steeplechase; 2018 Berlin gold: 3000 m steeplechase | |
| Luis Felipe Méliz | ATH | Olympics | 2000—2012 | 0–1–0 2012 Helsinki silver: long jump (competed for Spain) | |
| Faina Melnik | ATH | Olympics | 1972—1980 | 2–0–0 1971 Helsinki gold: discus throw; 1974 Roma gold: discus throw | |
| Stanislav Melnykov | ATH | Olympics | 2012 | 0–0–2 2010 Barcelona bronze: 400 m hurdles; 2012 Helsinki bronze: 400 m hurdles | |
| Hagen Melzer | ATH | Olympics | 1988—1992 | 1–0–0 1986 Stuttgart gold: 3000 m steeplechase (competed for East Germany) | |
| Kévin Ménaldo | ATH | Olympics | 2016 | 0–0–1 2014 Zürich bronze: pole vault | |
| Argentina Menis | ATH | Olympics | 1972—1976 | 0–1–0 1974 Roma silver: discus throw | |
| Pietro Mennea | ATH | Olympics / Opening Flagbearer | 1972—1988 | 3–2–1 1971 Helsinki bronze: 4×100 m relay; 1974 Roma gold: 200 m, silver: 100 m and 4×100 m relay; 1978 Praha gold: 100 m and 200 m | |
| Katharine Merry | ATH | Olympics | 1996—2000 | 0–0–1 1998 Budapest bronze: 4×400 m relay | |
| Štěpánka Mertová | ATH | Olympics | 1956—1960 | 0–1–0 1958 Stockholm silver: discus throw | |
| Romain Mesnil | ATH | Olympics | 2000—2012 | 0–1–0 2006 Göteborg silver: pole vault | |
| Adrian Metcalfe | ATH | Olympics | 1964 | 0–1–0 1962 Beograd silver: 4×400 m relay | |
| Gert Metz | ATH | Olympics | 1968 | 0–0–1 1966 Budapest bronze: 4×100 m relay | |
| Adolf Metzner | ATH | Olympics | 1932—1936 | 2–0–0 1934 Torino gold: 400 m and 4×400 m relay | |
| Daniele Meucci | ATH | Olympics | 2012—2024 | 1–1–3 2010 Barcelona bronze: 10000 m; 2012 Helsinki silver: 10000 m; 2014 Zürich gold: marathon; 2016 Amsterdam bronze: half-marathon and half-marathon team | |
| Monika Meyer | ATH | Non-starter | 1972—1976 | 0–0–1 1978 Praha bronze: 4×100 m relay | |
| Renate Meyer | ATH | Olympics | 1964—1968 | 0–1–0 1966 Budapest silver: 4×100 m relay (competed for West Germany) | |
| Ulrike Meyfarth | ATH | Olympics / Closing Flagbearer | 1972—1984 | 1–0–0 1982 Athina gold: high jump | |
| Detlef Michel | ATH | Olympics | 1980—1988 | 0–1–1 1982 Athina bronze: javelin throw; 1986 Stuttgart silver: javelin throw | |
| Ingrid Mickler-Becker | ATH | Olympics / Closing Flagbearer | 1960—1972 | 2–2–0 1969 Athina silver: 4×100 m relay (competed as Ingrid Becker for West Germany); 1971 Helsinki gold: 4×100 m relay and long jump, silver: 100 m (competed as Ingrid Mickler for West Germany) | |
| Yelena Migunova | ATH | Olympics | 2008 | 1–0–0 2006 Göteborg gold: 4×400 m relay (ran in heats only) | |
| Malaika Mihambo | ATH | Olympics | 2016—2024 | 1–0–1 2016 Amsterdam bronze: long jump; 2018 Berlin gold: long jump | |
| John Mikaelsson | ATH | Olympics | 1948—1952 | 1–0–1 1946 Oslo gold: 10 km walk; 1950 Bruxelles bronze: 10 km walk | |
| Anatoly Mikhaylov | ATH | Olympics | 1956—1964 | 1–0–1 1958 Stockholm bronze: 110 m hurdles; 1962 Beograd gold: 110 m hurdles | |
| Leonid Mikitenko | ATH | Olympics | 1968 | 0–0–1 1966 Budapest bronze: 10000 m | |
| Philip Milanov | ATH | Olympics | 2016—2024 | 0–1–0 2016 Amsterdam silver: discus throw | |
| Lothar Milde | ATH | Olympics | 1960—1968 | 0–1–3 1962 Beograd bronze: discus throw (competed for Germany); 1966 Budapest bronze: discus throw (competed for East Germany); 1969 Athina bronze: discus throw (competed for East Germany); 1971 Helsinki silver: discus throw (competed for East Germany) | |
| Ossi Mildh | ATH | Olympics | 1952—1956 | 0–0–2 1954 Bern bronze: 400 m hurdles and 4×400 m relay | |
| Roger Mills | ATH | Olympics | 1980 | 0–0–1 1974 Roma bronze: 20 km walk | |
| Alain Mimoun | ATH | Olympics | 1948—1960 | 0–2–0 1950 Bruxelles silver: 5000 m; and 10000 m | |
| Oleg Mishukov | ATH | Olympics | 2004 | 0–1–0 2002 München silver: 4×400 m relay | |
| Yauhen Misiulia | ATH | Olympics | 1988—2004 | 0–1–0 1994 Helsinki silver: 20 km walk (competed for Belarus) | |
| Nethaneel Mitchell-Blake | ATH | Olympics | 2016—2024 | 1–1–0 2018 Berlin gold: 4×100 m relay (ran in heats only), silver: 200 m | |
| Svetla Mitkova | ATH | Olympics | 1988—1996 | 0–0–1 1994 Helsinki bronze: shot put | |
| Gülcan Mıngır | ATH | Olympics | 2012 | 1–0–0 2012 Helsinki gold: 3000 m steeplechase | |
| Ivaylo Mladenov | ATH | Olympics | 1996 | 1–0–0 1994 Helsinki gold: long jump | |
| Vincenzo Modica | ATH | Olympics | 2000 | 0–0–1 1998 Budapest bronze: marathon | |
| Olga Modrachová | ATH | Olympics | 1952—1956 | 0–0–2 1950 Bruxelles bronze: pentathlon; 1954 Bern bronze: high jump | |
| Geir Moen | ATH | Olympics | 1996—2000 | 1–1–0 1994 Helsinki gold: 200 m, silver: 100 m | |
| Dietmar Mögenburg | ATH | Olympics | 1984—1992 | 1–0–0 1982 Athina gold: high jump (competed for West Germany) | |
| Antje Möldner-Schmidt | ATH | Olympics | 2008—2012 | 1–1–0 2012 Helsinki silver: 3000 m steeplechase; 2014 Zürich gold: 3000 m steeplechase | |
| Juan Manuel Molina | ATH | Olympics | 2004—2008 | 0–0–1 2002 München bronze: 20 km walk | |
| Michael Möllenbeck | ATH | Olympics | 1996—2004 | 0–0–1 2002 München bronze: discus throw | |
| Paula Mollenhauer | ATH | Olympics | 1928—1936 | 0–0–1 1938 Wien bronze: discus throw | |
| Silke Möller | ATH | Olympics | 1988 | 2–1–1 1986 Stuttgart gold: 4×100 m relay, bronze: 200 m (competed as Silke Gladisch); 1990 Split gold: 4×100 m relay, silver: 100 m | |
| Anne Möllinger-Cibis | ATH | Olympics | 2008—2012 | 1–0–0 2012 Helsinki gold: 4×100 m relay (competed as Anne Cibis) | |
| Werner von Moltke | ATH | Olympics | 1968 | 1–1–0 1962 Beograd silver: decathlon; 1966 Budapest gold: decathlon (competed for West Germany) | |
| Manuèla Montebrun | ATH | Olympics | 2000—2008 | 0–0–1 2002 München bronze: hammer throw | |
| Carlo Monti | ATH | Olympics | 1948 | 0–0–1 1946 Oslo bronze: 100 m | |
| Dave Moorcroft | ATH | Olympics | 1976—1984 | 0–0–2 1978 Praha bronze: 1500 m; 1982 Athina bronze: 5000 m | |
| Salvatore Morale | ATH | Olympics / Non-starter | 1960—1972 | 1–0–0 1962 Beograd gold: 400 m hurdles | |
| Dušan Moravčík | ATH | Olympics | 1972—1980 | 0–1–0 1971 Helsinki silver: 3000 m steeplechase | |
| Sara Moreira | ATH | Olympics | 2008—2020 | 2–1–1 2010 Barcelona silver: 5000 m; 2012 Helsinki bronze: 5000 m; 2016 Amsterdam gold: half-marathon and half-marathon team | |
| Fabrizio Mori | ATH | Olympics | 1992—2000 | 0–0–1 1998 Budapest bronze: 400 m hurdles | |
| Max Morinière | ATH | Olympics | 1988—1992 | 1–0–0 1990 Split gold: 4×100 m relay | |
| Aleksandr Morozov | ATH | Olympics | 1968 | 0–1–0 1969 Athina silver: 3000 m steeplechase | |
| Leonid Moseyev | ATH | Olympics | 1976—1980 | 1–0–0 1978 Praha gold: marathon | |
| Joseph Mostert | ATH | Olympics | 1936 | 0–1–0 1938 Paris silver: 1500 m | |
| Rosa Mota | ATH | Olympics / Closing Flagbearer | 1984—1988 | 3–0–0 1982 Athina gold: marathon; 1986 Stuttgart gold: marathon; 1990 Split gold: marathon | |
| Väinö Muinonen | ATH | Olympics | 1936 | 1–1–0 1938 Paris gold: marathon; 1946 Oslo silver: marathon | |
| Laura Muir | ATH | Olympics | 2016—2024 | 1–0–0 2018 Berlin gold: 1500 m | |
| Nadine Müller | ATH | Olympics | 2012—2016 | 0–2–0 2012 Helsinki silver: discus throw; 2018 Berlin silver: discus throw | |
| Petra Müller | ATH | Olympics | 1988 | 2–1–1 1986 Stuttgart gold: 4×400 m relay, bronze: 400 m; 1990 Split gold: 4×400 m relay, silver: 400 m | |
| Ángel Mullera | ATH | Olympics | 2012 | 0–0–1 2014 Zürich bronze: 3000 m steeplechase | |
| Kirsten Münchow | ATH | Olympics | 2000 | 0–0–1 1998 Budapest bronze: hammer throw | |
| Antónia Munkácsi | ATH | Olympics | 1960—1968 | 0–1–0 1966 Budapest silver: 400 m | |
| Thomas Munkelt | ATH | Olympics | 1976—1980 | 2–1–0 1978 Praha gold: 110 m hurdles; 1982 Athina gold: 110 m hurdles, silver: 4×100 m relay | |
| Vladimir Muravyov | ATH | Olympics | 1980—1988 | 1–0–0 1986 Stuttgart gold: 4×100 m relay | |
| Lyudmila Muravyova | ATH | Olympics | 1968—1972 | 0–1–1 1969 Athina silver: discus throw; 1971 Helsinki bronze: discus throw | |
| Frank Murphy | ATH | Olympics | 1968—1972 | 0–1–0 1969 Athina silver: 1500 m | |
| Yvonne Murray | ATH | Olympics | 1988—1992 | 1–1–1 1986 Stuttgart bronze: 3000 m; 1990 Split gold: 3000 m; 1994 Helsinki silver: 3000 m | |
| Maria Musso | ATH | Olympics | 1952—1956 | 0–0–1 1954 Bern bronze: 4×100 m relay | |
| Peter Muster | ATH | Olympics | 1976 | 0–0–1 1978 Praha bronze: 200 m | |
| Jiří Mužík | ATH | Olympics | 2000—2004 | 0–1–0 2002 München silver: 400 m hurdles | |
| Lubomír Nádeníček | ATH | Olympics | 1968—1972 | 0–0–1 1971 Helsinki bronze: 110 m hurdles | |
| Koen Naert | ATH | Olympics | 2016—2024 | 1–0–0 2018 Berlin gold: marathon | |
| Gerd Nagel | ATH | Olympics | 1984 | 0–0–1 1982 Athina bronze: high jump | |
| Jean-Claude Nallet | ATH | Olympics | 1968—1976 | 2–2–1 1966 Budapest bronze: 200 m; 1969 Athina gold: 4×400 m relay, silver: 400 m; 1971 Helsinki gold: 400 m hurdles; 1974 Roma silver: 400 m hurdles | |
| Antoinette Nana Djimou | ATH | Olympics | 2008—2016 | 2–1–0 2012 Helsinki gold: heptathlon; 2014 Zürich gold: heptathlon; 2016 Amsterdam silver: heptathlon | |
| Bill Nankeville | ATH | Olympics | 1948—1952 | 0–0–1 1950 Bruxelles bronze: 1500 m | |
| Daria Nauer | ATH | Olympics | 1996—2000 | 0–0–1 1994 Helsinki bronze: 10000 m | |
| Nataliya Nazarova | ATH | Olympics | 2000—2012 | 0–1–0 2002 München silver: 4×400 m relay | |
| Karl Neckermann | ATH | Olympics | 1936 | 1–0–0 1938 Paris gold: 4×100 m relay | |
| Anita Neil | ATH | Olympics | 1968—1972 | 0–0–2 1969 Athina bronze: 100 m and 4×100 m relay | |
| Kathrin Neimke | ATH | Olympics | 1988—1996 | 0–0–1 1990 Split bronze: shot put (competed for East Germany) | |
| Daryll Neita | ATH | Olympics | 2016—2024 | 1–1–0 2016 Amsterdam silver: 4×100 m relay; 2018 Berlin gold: 4×100 m relay (ran in heats only) | |
| Ashleigh Nelson | ATH/BOB | Olympics / Non-starter | 2008—2026 | 1–0–1 2014 Zürich gold: 4×100 m relay, bronze: 100 m | |
| Angéla Németh-Ránky | ATH | Olympics | 1968—1972 | 1–0–0 1969 Athina gold: javelin throw (competed as Angéla Németh) | |
| Roland Németh | ATH | Olympics | 2004 | 0–0–1 2002 München bronze: 100 m | |
| Steffi Nerius | ATH | Olympics | 1996—2008 | 1–1–0 2002 München silver: javelin throw; 2006 Göteborg gold: javelin throw | |
| Yuliya Nestsiarenka | ATH | Olympics | 2004—2008 | 0–0–1 2006 Göteborg bronze: 4×100 m relay | |
| Dagmar Neubauer | ATH | Olympics / Non-starter | 1980—1988 | 1–0–0 1982 Athina gold: 4×400 m relay (competed as Dagmar Rübsam) | |
| Ramona Neubert | ATH | Olympics | 1980 | 1–0–0 1982 Athina gold: heptathlon | |
| Josef Neumann | ATH | Olympics | 1936 | 0–0–1 1938 Paris bronze: decathlon | |
| Klaus Neumann | ATH | Olympics | 1968 | 0–0–1 1969 Athina bronze: triple jump | |
| Alena Neumiarzhitskaya-Daniliok | ATH | Olympics | 2004—2012 | 0–0–1 2006 Göteborg bronze: 4×100 m relay (competed as Alena Neumiarzhitskaya) | |
| Pauli Nevala | ATH | Olympics | 1964—1968 | 0–1–0 1969 Athina silver: javelin throw | |
| Nils Nicklén | ATH | Olympics | 1948 | 0–0–1 1946 Oslo bronze: high jump | |
| Christian Nicolau | ATH | Olympics | 1968 | 1–0–0 1969 Athina gold: 4×400 m relay | |
| Gunnar Nielsen | ATH | Olympics | 1952—1956 | 0–1–0 1954 Bern silver: 1500 m | |
| Henry Nielsen | ATH | Olympics / Non-starter | 1928—1936 | 0–0–1 1934 Torino bronze: 10000 m | |
| Paul Nihill | ATH | Olympics | 1964—1976 | 1–0–1 1969 Athina gold: 20 km walk; 1971 Helsinki bronze: 20 km walk | |
| Gerard Nijboer | ATH | Olympics | 1980—1988 | 1–0–0 1982 Athina gold: marathon | |
| Władysław Nikiciuk | ATH | Olympics | 1964—1968 | 0–1–1 1962 Beograd bronze: javelin throw; 1966 Budapest silver: javelin throw | |
| Yrjö Nikkanen | ATH | Olympics | 1936 | 0–2–0 1938 Paris silver: javelin throw; 1946 Oslo silver: javelin throw | |
| Soini Nikkinen | ATH | Olympics | 1948—1952 | 0–0–1 1954 Bern bronze: javelin throw | |
| Yelena Nikolayeva | ATH | Olympics | 1992—2004 | 0–1–1 1994 Helsinki bronze: 10 km walk (competed for Russia); 2002 München silver: 20 km walk (competed for Russia) | |
| Vera Nikolić | ATH | Olympics | 1968—1972 | 2–0–1 1966 Budapest gold: 800 m; 1969 Athina bronze: 800 m; 1971 Helsinki gold: 800 m | |
| Pentti Nikula | ATH | Olympics | 1964 | 1–0–0 1962 Beograd gold: pole vault | |
| Igor Nikulin | ATH | Olympics | 1992 | 0–1–2 1982 Athina silver: hammer throw (competed for the Soviet Union); 1986 Stuttgart bronze: hammer throw (competed for the Soviet Union); 1990 Split bronze: hammer throw (competed for the Soviet Union) | |
| Bengt Nilsson | ATH | Olympics | 1956 | 1–0–0 1954 Bern gold: high jump | |
| Artur Noga | ATH | Olympics | 2008—2012 | 0–0–1 2012 Helsinki bronze: 110 m hurdles | |
| Monique Noirot | ATH | Olympics | 1968 | 0–0–1 1966 Budapest bronze: 400 m | |
| Erki Nool | ATH | Olympics / Opening Flagbearer | 1992—2004 | 1–1–0 1998 Budapest gold: decathlon; 2002 München silver: decathlon | |
| Wolfgang Nordwig | ATH | Olympics | 1968—1972 | 3–0–0 1966 Budapest gold: pole vault; 1969 Athina gold: pole vault; 1971 Helsinki gold: pole vault | |
| Roger Norman | ATH | Olympics | 1952 | 0–1–0 1954 Bern silver: triple jump | |
| Harald Norpoth | ATH | Olympics | 1964—1972 | 0–1–2 1966 Budapest silver: 5000 m, bronze: 1500 m (competed for West Germany); 1971 Helsinki bronze: 5000 m (competed for West Germany) | |
| Fred Norris | ATH | Olympics | 1952—1956 | 0–0–1 1958 Stockholm bronze: marathon | |
| Marcin Nowak | ATH | Olympics | 2000—2008 | 0–1–1 1998 Budapest bronze: 4×100 m relay; 2002 München silver: 4×100 m relay | |
| Teresa Nowak | ATH | Olympics | 1972 | 0–0–2 1969 Athina bronze: 100 m hurdles; 1974 Roma bronze: 100 m hurdles | |
| Wojciech Nowicki | ATH | Olympics | 2016—2024 | 1–0–1 2016 Amsterdam bronze: hammer throw; 2018 Berlin gold: hammer throw | |
| Zenon Nowosz | ATH | Olympics | 1968—1976 | 1–1–1 1969 Athina bronze: 200 m; 1971 Helsinki silver: 4×100 m relay; 1978 Praha gold: 4×100 m relay | |
| Brigitte Ntiamoah | ATH | Olympics | 2016—2020 | 0–1–0 2016 Amsterdam silver: 4×400 m relay | |
| Liliya Nurutdinova | ATH | Olympics | 1992 | 0–0–1 1990 Split bronze: 800 m (competed for the Soviet Union) | |
| Evert Nyberg | ATH | Olympics | 1948—1960 | 0–0–1 1946 Oslo bronze: 5000 m | |
| Jarmila Nygrýnová | ATH | Olympics | 1972—1980 | 0–0–1 1978 Praha bronze: long jump | |
| Sven Nylander | ATH | Olympics / Non-starter | 1984—1996 | 0–2–1 1986 Stuttgart bronze: 400 m hurdles; 1990 Split silver: 400 m hurdles; 1994 Helsinki silver: 400 m hurdles | |
| Veikko Nyqvist | ATH | Olympics | 1948—1952 | 0–0–1 1946 Oslo bronze: discus throw | |
| Carolin Nytra | ATH | Olympics | 2008—2012 | 0–0–1 2010 Barcelona bronze: 100 m hurdles | |
| Eva Nývltová-Vrabcová | ATH/CCS | Olympics | 2006—2020 | 0–0–1 2018 Berlin bronze: marathon | |
| Chris O'Hare | ATH | Olympics | 2016 | 0–0–1 2014 Zürich bronze: 1500 m | |
| Derval O'Rourke | ATH | Olympics | 2004—2012 | 0–2–0 2006 Göteborg silver: 100 m hurdles; 2010 Barcelona silver: 100 m hurdles | |
| Sonia O'Sullivan | ATH | Olympics / Opening Flagbearer | 1992—2004 | 3–2–0 1994 Helsinki gold: 3000 m; 1998 Budapest gold: 5000 m and 10000 m; 2002 München silver: 5000 m and 10000 m | |
| Christina Obergföll | ATH | Olympics | 2004—2016 | 0–2–0 2010 Barcelona silver: javelin throw; 2012 Helsinki silver: javelin throw | |
| Giorgio Oberweger | ATH | Olympics | 1936—1948 | 0–1–0 1938 Paris silver: discus throw | |
| Francis Obikwelu | ATH | Olympics | 1996—2008 | 3–1–0 2002 München gold: 100 m, silver: 200 m (competed for Portugal); 2006 Göteborg gold: 100 m and 200 m (competed for Portugal) | |
| Dorothy Odam-Tyler | ATH | Olympics | 1936—1956 | 0–1–0 1950 Bruxelles silver: high jump | |
| Marlies Oelsner-Göhr | ATH | Olympics | 1976—1988 | 5–1–1 1978 Praha gold: 100 m, silver: 200 m, bronze: 4×100 m relay (competed as Marlies Göhr); 1982 Athina gold: 100 m and 4×100 m relay (competed as Marlies Göhr); 1986 Stuttgart gold: 100 m and 4×100 m relay (competed as Marlies Göhr) | |
| Jennifer Oeser | ATH | Olympics | 2008—2016 | 0–0–1 2010 Barcelona bronze: heptathlon | |
| Marilyn Okoro | ATH | Olympics | 2008 | 0–1–0 2010 Barcelona silver: 4×400 m relay | |
| Antonina Okorokova-Lazareva | ATH | Olympics | 1968—1972 | 0–1–0 1969 Athina silver: high jump (competed as Antonina Lazareva) | |
| Valto Olenius | ATH | Olympics | 1948—1952 | 0–1–0 1950 Bruxelles silver: pole vault | |
| Annelise Damm Olesen | ATH | Olympics | 1968—1972 | 0–1–0 1969 Athina silver: 800 m | |
| Margrit Olfert | ATH | Olympics | 1972 | 0–0–1 1971 Helsinki bronze: pentathlon (competed as Margrit Herbst) | |
| Anna Olichwierczuk-Jesień | ATH | Olympics | 2000—2012 | 0–0–3 2002 München bronze: 400 m hurdles and 4×400 m relay (competed as Anna Olichwierczuk); 2006 Göteborg bronze: 4×400 m relay (competed as Anna Jesień) | |
| Staņislavs Olijars | ATH | Olympics / Non-starter | 2000—2008 | 1–1–0 2002 München silver: 110 m hurdles; 2006 Göteborg gold: 110 m hurdles | |
| Yuliya Olishevska | ATH | Olympics | 2016 | 1–0–0 2012 Helsinki gold: 4×400 m relay | |
| Nadezhda Olizarenko | ATH | Olympics | 1980—1988 | 1–2–0 1978 Praha silver: 800 m and 4×400 m relay (competed as Nadezhda Mushta); 1986 Stuttgart gold: 800 m | |
| Manuel Olmedo | ATH | Olympics | 2004—2008 | 0–0–1 2010 Barcelona bronze: 1500 m | |
| Joachim Olsen | ATH | Olympics / Opening Flagbearer / Closing Flagbearer | 2000—2008 | 0–2–0 2002 München silver: shot put; 2006 Göteborg silver: shot put | |
| Christian Olsson | ATH | Olympics / Opening Flagbearer | 2000—2008 | 2–0–0 2002 München gold: triple jump; 2006 Göteborg gold: triple jump | |
| Rafał Omelko | ATH | Olympics | 2016 | 0–1–1 2014 Zürich bronze: 4×400 m relay; 2016 Amsterdam silver: 4×400 m relay | |
| Manfred Ommer | ATH | Olympics | 1972 | 0–1–0 1974 Roma silver: 200 m | |
| Eike Onnen | ATH | Olympics | 2016 | 0–0–1 2016 Amsterdam bronze: high jump | |
| Anyika Onuora | ATH | Olympics / Non-starter | 2008—2016 | 2–1–2 2006 Göteborg silver: 4×100 m relay; 2014 Zürich gold: 4×100 m relay (ran in heats only); 2016 Amsterdam gold: 4×400 m relay, bronze: 400 m; 2018 Berlin bronze: 4×400 m relay | |
| Marian Oprea | ATH | Olympics / Closing Flagbearer | 2004—2016 | 0–1–1 2006 Göteborg bronze: triple jump; 2010 Barcelona silver: triple jump | |
| Jan Ornoch | ATH | Olympics | 1972—1976 | 0–0–1 1978 Praha bronze: 50 km walk | |
| Orlando Ortega | ATH | Olympics / Non-starter | 2012—2020 | 0–0–1 2018 Berlin bronze: 110 m hurdles (competed for Spain) | |
| Venanzio Ortis | ATH | Olympics | 1976 | 1–1–0 1978 Praha gold: 5000 m, silver: 10000 m | |
| Cornelia Oschkenat | ATH | Olympics | 1988 | 0–1–0 1986 Stuttgart silver: 100 m hurdles | |
| Tinus Osendarp | ATH | Olympics | 1936 | 2–0–2 1934 Torino bronze: 200 m and 4×100 m relay; 1938 Paris gold: 100 m and 200 m | |
| Şeref Osmanoğlu | ATH | Olympics | 2012—2016 | 0–1–0 2012 Helsinki silver: triple jump (competed as Sheryf El-Sheryf for Ukraine) | |
| Matic Osovnikar | ATH | Olympics | 2000—2008 | 0–0–1 2006 Göteborg bronze: 100 m | |
| Serhiy Osovych | ATH | Olympics | 1996 | 0–1–0 1994 Helsinki silver: 4×100 m relay | |
| Juan Carlos de la Ossa | ATH | Olympics | 2008 | 0–0–1 2006 Göteborg bronze: 10000 m | |
| Maire Österdahl | ATH | Olympics | 1952 | 0–0–1 1950 Bruxelles bronze: long jump | |
| Micheline Ostermeyer | ATH | Olympics | 1948 | 0–1–2 1946 Oslo silver: shot put; 1950 Bruxelles bronze: 80 m hurdles and shot put | |
| Ronny Ostwald | ATH | Olympics / Non-starter | 2004—2008 | 0–0–1 2002 München bronze: 4×100 m relay | |
| Anita Otto | ATH | Olympics | 1968 | 0–0–1 1966 Budapest bronze: discus throw (competed as Anita Hentschel) | |
| Björn Otto | ATH | Olympics | 2012 | 0–1–0 2012 Helsinki silver: pole vault | |
| Sergio Ottolina | ATH | Olympics / Non-starter | 1960—1968 | 0–0–1 1962 Beograd bronze: 200 m | |
| Eddy Ottoz | ATH | Olympics | 1964—1968 | 2–0–0 1966 Budapest gold: 110 m hurdles; 1969 Athina gold: 110 m hurdles | |
| Olena Ovcharova-Krasovska | ATH | Olympics | 1996—2004 | 0–1–0 2002 München silver: 100 m hurdles (competed as Olena Krasovska) | |
| Steve Ovett | ATH | Olympics | 1976—1984 | 1–2–0 1974 Roma silver: 800 m; 1978 Praha gold: 1500 m, silver: 800 m | |
| Kaan Kigen Özbilen | ATH | Olympics | 2016—2024 | 0–1–0 2016 Amsterdam silver: half-marathon | |
| Edvin Ozolin | ATH | Olympics | 1960—1964 | 0–1–1 1958 Stockholm bronze: 4×100 m relay; 1966 Budapest silver: 4×100 m relay | |
| Elvīra Ozoliņa | ATH | Olympics | 1960—1964 | 1–0–0 1962 Beograd gold: javelin throw | |
| Ann Packer | ATH | Olympics | 1964 | 0–0–1 1962 Beograd bronze: 4×100 m relay | |
| Ernie Page | ATH | Olympics | 1932 | 0–0–1 1938 Paris bronze: 4×100 m relay | |
| Igor Paklin | ATH | Olympics | 1988—1992 | 1–0–0 1986 Stuttgart gold: high jump (competed for the Soviet Union) | |
| Henry Palmé | ATH | Olympics | 1936 | 0–0–1 1938 Paris bronze: marathon | |
| Antonella Palmisano | ATH | Olympics | 2016—2024 | 0–0–1 2018 Berlin bronze: 20 km walk | |
| Airinė Palšytė | ATH | Olympics | 2012—2024 | 0–1–0 2016 Amsterdam silver: high jump | |
| Uno Palu | ATH | Olympics | 1956 | 0–1–0 1958 Stockholm silver: decathlon | |
| Abdon Pamich | ATH | Olympics / Opening Flagbearer | 1956—1972 | 2–1–0 1958 Stockholm silver: 50 km walk; 1962 Beograd gold: 50 km walk; 1966 Budapest gold: 50 km walk | |
| Manuel Pancorbo | ATH | Olympics | 1992—1996 | 0–1–0 1998 Budapest silver: 5000 m | |
| Brice Panel | ATH | Olympics | 2008 | 1–0–0 2006 Göteborg gold: 4×400 m relay (ran in heats only) | |
| Francesco Panetta | ATH | Olympics | 1984—1988 | 1–1–0 1986 Stuttgart silver: 3000 m steeplechase; 1990 Split gold: 3000 m steeplechase | |
| Ans Panhorst-Niesink | ATH | Olympics | 1936—1948 | 0–1–0 1946 Oslo silver: discus throw | |
| Paraskevi Papachristou | ATH | Olympics | 2016—2020 | 1–0–1 2016 Amsterdam bronze: triple jump; 2018 Berlin gold: triple jump | |
| Charalampos Papadias | ATH | Olympics | 1996 | 0–0–1 1998 Budapest bronze: 100 m |