Host cities:
| Athlete | Nation(s) | Sport(s) | Role(s) | Era | Notes |
|---|---|---|---|---|---|
| Patrick Abada | ATH | Olympics | 1976 | 0–0–1 1979 Ciudad de México ATH bronze: pole vault | |
| Patimat Abakarova | TKW | Olympics | 2016 | 0–0–1 2019 Napoli TKW bronze: bantamweight -53 kg | |
| Mariya Abakumova | ATH | Olympics | 2008—2012 | 1–0–0 2013 Kazan ATH gold: javelin throw | |
| Jesús Aballí | DIV | Olympics | 2000 | 0–0–2 1997 Catania DIV bronze: platform; 1999 Palma de Mallorca DIV bronze: platform | |
| Emanuele Abate | ATH | Olympics | 2012 | 0–0–1 2009 Beograd ATH bronze: 110 m hurdles | |
| Péter Abay | FEN | Olympics | 1992 | 1–0–0 1987 Zagreb FEN gold: sabre team | |
| Reema Abdo | SWM | Olympics | 1984 | 0–0–1 1983 Edmonton SWI bronze: 4×100 m medley relay | |
| Ruky Abdulai | ATH | Olympics | 2008 | 0–0–1 2009 Beograd ATH bronze: long jump | |
| Adlan Abdurashidov | BOX | Olympics | 2016 | 1–0–0 2013 Kazan BOX gold: lightweight -60 kg | |
| Naoki Abe | ATH | Olympics | 1968 | 1–1–0 1967 Tokyo ATH gold: long jump, silver: 4×100 m relay | |
| Ismail Abilov | WRE | Olympics | 1976—1980 | 0–0–1 1977 Sofia WRE bronze: freestyle middleweight -82 kg | |
| Denis Ablyazin | GAR | Olympics | 2012—2020 | 1–2–0 2013 Kazan GYM gold: team, silver: vault and rings | |
| Viktor Aboimov | SWM | Olympics | 1972 | 1–2–0 1970 Torino SWI silver: 4×200 m freestyle relay; 1973 Moskva SWI gold: 4×200 m freestyle relay, silver: 4×100 m freestyle relay | |
| Attila Ábrahám | CSP | Olympics | 1988—1992 | 1–0–1 1987 Zagreb CAN gold: K4 1000 m, bronze: K1 500 m | |
| Göran Abrahamsson | FEN | Olympics / Referee | 1960—1992 | 0–0–1 1959 Torino FEN bronze: épée | |
| Alena Abramchuk | ATH | Olympics | 2016 | 0–0–1 2009 Beograd ATH bronze: shot put (competed as Yelena Kopets) | |
| Andrey Abramov | ARC | Olympics | 2008 | 0–0–1 2005 İzmir ARC bronze: recurve team | |
| Inna Abramova | SWM | Olympics | 1988 | 2–0–0 1985 Kobe SWI gold: 4×100 m freestyle relay and 4×200 m freestyle relay | |
| Nelli Abramova | VVO | Olympics | 1964 | 1–0–0 1965 Budapest VOL gold | |
| Svetlana Abrosimova | BKB | Olympics | 2000—2008 | 0–0–1 1999 Palma de Mallorca BAS bronze | |
| Roberto Abugattás | ATH | Olympics | 1964—1968 | 0–0–1 1963 Porto Alegre ATH bronze: high jump | |
| Ahmad Abughaush | TKW | Olympics / Closing Flagbearer | 2016 | 0–0–1 2017 Taipei TKW bronze: featherweight -68 kg | |
| Aleksandr Abushakhmetov | FEN | Olympics | 1976—1980 | 0–1–1 1977 Sofia FEN bronze: épée team; 1979 Ciudad de México FEN silver: épée team | |
| Jaouad Achab | TKW | Olympics | 2016—2020 | 1–0–0 2015 Gwangju TKW gold: bantamweight -63 kg | |
| Georg Ackermann | ATH | Olympics | 1996 | 0–1–0 1995 Fukuoka ATH silver: long jump | |
| Briseida Acosta | TKW | Olympics / YOG | 2010—2020 | 0–0–1 2017 Taipei TKW bronze: heavyweight +73 kg | |
| Amy Acuff | ATH | Olympics | 1996—2012 | 1–0–0 1997 Catania ATH gold: high jump | |
| Patrycja Adamkiewicz | TKW | Olympics / YOG | 2014—2020 | 0–1–2 2017 Taipei TKW silver: Kyorugi team; 2019 Napoli bronze: featherweight -57 kg and Kyorugi team | |
| Olapade Adeniken | ATH | Olympics | 1988—1996 | 0–1–0 1989 Duisburg ATH silver: 100 m | |
| Derrick Adkins | ATH | Olympics | 1996 | 2–0–0 1991 Sheffield ATH gold: 400 m hurdles; 1993 Buffalo ATH gold: 400 m hurdles | |
| Elisângela Adriano | ATH | Olympics | 1996—2008 | 0–0–2 1999 Palma de Mallorca ATH bronze: shot put and discus throw | |
| Serhiy Advena | SWM | Olympics | 2004—2008 | 1–1–1 2003 Daegu SWI silver: 200 m butterfly; 2005 İzmir SWI gold: 4×100 m medley relay, bronze: 100 m butterfly | |
| Sara Aerts | ATH/BOB | Olympics | 2012—2022 | 0–1–0 2007 Bangkok ATH silver: heptathlon | |
| Kseniya Afanasyeva | GAR | Olympics | 2008—2012 | 3–1–0 2013 Kazan GYM gold: floor, vault, and team, silver: all-around | |
| Leonardo Affede | FEN | YOG | 2010 | 0–0–1 2015 Gwangju FEN bronze: sabre | |
| Bisi Afolabi | ATH | Olympics | 1996—2000 | 1–0–1 1993 Buffalo ATH bronze: 4×400 m relay; 1995 Fukuoka ATH gold: 400 m | |
| Ajayi Agbebaku | ATH | Olympics | 1984 | 1–0–0 1983 Edmonton ATH gold: triple jump | |
| Judit Ágoston-Mendelényi | FEN | Olympics | 1964 | 0–1–1 1963 Porto Alegre FEN silver: foil team, bronze: foil | |
| Judith Águila | BKB | Olympics | 1992—1996 | 0–1–0 1993 Buffalo BAS silver | |
| Jorge Aguilera | ATH | Olympics | 1992 | 0–0–1 1993 Buffalo ATH bronze: 4×100 m relay | |
| Juan Aguirre | ROW | Olympics | 1992 | 0–1–0 1989 Duisburg ROW silver: lightweight coxless fours | |
| Sri Wahyuni Agustiani | WLF | Olympics | 2016 | 0–0–1 2017 Taipei WLT bronze: flyweight -48 kg | |
| Tontowi Ahmad | BDM | Olympics | 2012—2016 | 0–0–1 2007 Bangkok BDM bronze: team | |
| Stefan Ahrens | DIV | Olympics | 2000 | 0–0–1 2001 Beijing DIV bronze: synchronized springboard | |
| Mohammad Ahsan | BDM | Olympics | 2012—2020 | 0–0–1 2007 Bangkok BDM bronze: team | |
| Pasquale Aiese | ROW | Olympics | 1984 | 0–0–1 1987 Zagreb ROW bronze: coxless pairs | |
| Yutaka Aihara | GAR | Olympics | 1992 | 0–2–2 1991 Sheffield GYM silver: floor and team, bronze: horse vault and parallel bars | |
| Samir Aït Saïd | GAR | Olympics / Opening Flagbearer | 2016—2024 | 0–1–0 2011 Shenzhen GYM silver: rings | |
| Marina Aitova | ATH | Olympics / Non-starter | 2004—2012 | 1–0–0 2007 Bangkok ATH gold: high jump | |
| Zita Ajkler | ATH | Olympics | 2000—2004 | 0–0–1 2003 Daegu ATH bronze: long jump | |
| Yukiko Akaba | ATH | Olympics | 2008 | 0–1–1 1999 Palma de Mallorca ATH silver: half marathon; 2001 Beijing ATH bronze: 10000 m | |
| Egamnazar Akbarov | JUD | Olympics | 2004 | 1–0–0 2001 Beijing JUD gold: lightweight -73 kg | |
| Taha Akgül | WRE | Olympics / Closing Flagbearer | 2012—2024 | 1–0–0 2013 Kazan WRE gold: freestyle super-heavyweight -120 kg | |
| Artur Akhmatkhuzin | FEN | Olympics | 2012—2016 | 2–0–1 2009 Beograd FEN gold: foil team; 2011 Shenzhen FEN bronze: foil team; 2013 Kazan FEN gold: foil team | |
| Nataliya Akhrimenko | ATH | Olympics | 1980—1988 | 0–1–1 1983 Edmonton ATH silver: discus throw, bronze: shot put | |
| Lade Akinremi | ATH | Olympics / Non-starter | 1996—2004 | 0–0–1 1993 Buffalo ATH bronze: 4×400 m relay | |
| Halil Akkaş | ATH | Olympics | 2008—2016 | 4–2–0 2005 İzmir ATH gold: 3000 m steeplechase; 2007 Bangkok ATH gold: 5000 m and 3000 m steeplechase; 2009 Beograd ATH gold: 5000 m, silver: 3000 m steeplechase; 2011 Shenzhen ATH silver: 3000 m steeplechase | |
| Ime Akpan | ATH | Olympics | 1996 | 0–0–1 1995 Fukuoka ATH bronze: 4×100 m relay | |
| Aleksandr Aksinin | ATH | Olympics | 1976—1980 | 1–1–0 1977 Sofia ATH gold: 4×100 m relay; 1981 București ATH silver: 4×100 m relay | |
| Ohenewa Akuffo | WRE | Olympics | 2008 | 1–0–0 2005 İzmir WRE gold: freestyle heavyweight -72 kg | |
| Taiwo Aladefa | ATH | Olympics | 1996 | 0–0–1 1995 Fukuoka ATH bronze: 4×100 m relay | |
| Päivi Alafrantti | ATH | Olympics | 1988—1992 | 0–0–1 1989 Duisburg ATH bronze: javelin throw | |
| Michèle Alayrangues | ATH | Olympics | 1968 | 1–0–0 1967 Tokyo ATH gold: 4×100 m relay | |
| Toni Albanese | FEN | Olympics | 1968 | 1–0–1 1961 Sofia FEN gold: épée team; 1963 Porto Alegre FEN bronze: épée team | |
| Ruslan Albegov | WLF | Olympics | 2012 | 1–0–0 2013 Kazan WLT gold: super-heavyweight +105 kg | |
| Pierre Albertini | JUD | Olympics | 1972 | 0–0–1 1967 Tokyo JUD bronze: half-middleweight -93 kg | |
| Islam-Beka Albiyev | WRE | Olympics | 2008—2016 | 0–1–0 2013 Kazan WRE silver: Greco-Roman welterweigth -66 kg | |
| María José Alcalá | DIV | Olympics / Administrator | 1988—2021 | 0–1–1 1995 Fukuoka DIV silver: 3 m springboard; 1997 Catania DIV bronze: 3 m springboard | |
| Jannet Alegría | TKW | Olympics | 2012 | 0–0–2 2007 Bangkok TKW bronze: flyweight -51 kg; 2009 Beograd TKW bronze: flyweight -51 kg | |
| Mihail Aleksandrov | SWM | Olympics | 2004—2008 | 0–1–1 2013 Kazan SWI silver: 100 m breaststroke, bronze: 4×100 m medley relay (competed for the United States) | |
| Dmitry Aleksanin | FEN | Olympics | 2012 | 0–0–1 2013 Kazan FEN bronze: épée team | |
| Artur Aleksanyan | WRE | Olympics / Closing Flagbearer | 2012—2024 | 0–1–0 2013 Kazan WRE silver: Heavyweight Greco-Roman | |
| Milan Aleksić | WPO | Olympics | 2012—2020 | 1–0–0 2005 İzmir WAP gold | |
| Constantin Alexandru | WRE | Olympics | 1976—1980 | 1–1–0 1977 Sofia WRE gold: Greco-Roman light-flyweight -48 kg; 1981 București WRE silver: Greco-Roman light-flyweight -48 kg | |
| Vladimir Aleynik | DIV | Olympics | 1976—1980 | 1–0–1 1979 Ciudad de México DIV gold: platform; 1981 București DIV bronze: platform | |
| Mohamed Sid Ali Djouadi | ATH | Olympics | 1972 | 0–0–1 1975 Roma ATH bronze: 800 m | |
| Ahmed Ali Saleh | TTE | Olympics | 2008—2020 | 0–0–1 2001 Beijing TTN bronze: team | |
| Nia Ali | ATH | Olympics | 2016 | 1–0–0 2011 Shenzhen ATH gold 100 m hurdles | |
| Elmir Alimzhanov | FEN | Olympics | 2012—2024 | 0–0–1 2013 Kazan FEN bronze: épée team | |
| Diane Allahgreen | ATH | Olympics | 2000 | 0–0–1 1999 Palma de Mallorca ATH bronze: 100 m hurdles | |
| Kanati Allen | GAR | Olympics | 1968 | 0–1–0 1967 Tokyo GYM silver: team | |
| Liliana Allen | ATH | Olympics | 1992—2004 | 1–2–0 1989 Duisburg ATH gold: 100 m, silver: 200 m (competed for Cuba); 1993 Buffalo ATH silver: 100 m (competed for Cuba) | |
| Ray Allen | BKB | Olympics | 2000 | 1–0–0 1995 Fukuoka BAS gold | |
| Yusuf Alli | ATH | Olympics / Opening Flagbearer | 1980—1988 | 1–0–0 1983 Edmonton ATH gold: long jump | |
| Audrey Alloh | ATH | Olympics | 2008 | 1–0–0 2009 Beograd ATH gold: 4×100 m relay | |
| Lynne Allsup | SWM | Olympics | 1964 | 1–1–0 1967 Tokyo SWI gold: 4×100 m freestyle relay, silver: 100 m freestyle | |
| Rose Almanza | ATH | Olympics | 2012—2024 | 1–0–0 2017 Taipei ATH gold: 800 m | |
| Michel Almeida | JUD | Olympics | 1996—2000 | 0–0–1 1999 Palma de Mallorca JUD bronze: lightweight -73 kg | |
| Maria Laura Almirão | ATH | Olympics | 2004—2008 | 0–1–0 2001 Beijing ATH silver: 4×100 m relay | |
| Mohamed Alouini | ATH | Olympics | 1984 | 0–0–1 1983 Edmonton ATH bronze: 800 m | |
| Misha Aloyan | BOX | Olympics | 2012—2016 | 0–1–0 2013 Kazan BOX silver: flyweight -52 kg | |
| Andrey Alshan | FEN | Olympics | 1988 | 1–2–0 1981 București FEN silver: sabre and sabre team; 1985 Kobe FEN gold: sabre team | |
| Juan María Altuna | ROW | Olympics | 1992 | 0–1–0 1989 Duisburg ROW silver: lightweight coxless fours | |
| Dorin Alupei | ROW | Olympics | 1996—2000 | 1–0–0 1993 Buffalo ROW gold: coxed fours | |
| José Miguel Álvarez | BKB | Olympics | 1972 | 0–0–1 1970 Torino BAS bronze | |
| Rafael Álvarez | DIV | Olympics | 1992—2000 | 0–0–1 1999 Palma de Mallorca DIV bronze: 3 m springboard | |
| Ana Álvaro | BKB | Olympics | 1992 | 0–1–0 1991 Sheffield BAS silver | |
| Thiago Alves | VVO | Olympics | 2012 | 0–0–1 2011 Shenzhen VOL bronze | |
| Nikolay Alyokhin | FEN | Olympics | 1980 | 1–0–0 1979 Ciudad de México FEN gold: sabre team | |
| Yevgeny Alyoshin | SWM | Olympics | 2004 | 0–1–0 1999 Palma de Mallorca SWI silver: 4×100 m medley relay (swam in heats only) | |
| Akgul Amanmuradova | TEN | Olympics | 2008 | 0–0–1 2003 Daegu TEN bronze: singles | |
| Amaury | BKB | Olympics | 1956—1964 | 1–0–0 1963 Porto Alegre BAS gold | |
| Miklós Ambrus | SWM/WPO | Olympics / Non-starter | 1960—1964 | 0–0–1 1961 Sofia WAP bronze | |
| Henry Amike | ATH | Olympics | 1984—1988 | 0–1–0 1985 Kobe ATH silver: 400 m hurdles | |
| Vladislav Aminov | SWM | Olympics | 2000 | 0–1–1 1997 Catania SWI bronze: 4×100 m medley relay; 1999 Palma de Mallorca SWI silver: 4×100 m medley relay | |
| Savitree Amitrapai | BDM | Olympics | 2016 | 0–0–4 2011 Shenzhen BDM bronze: doubles, mixed doubles, and team; 2013 Kazan BDM bronze: team | |
| Agapius Amo | ATH | Olympics | 1984 | 0–1–0 1983 Edmonton ATH silver: 10000 m | |
| Nijel Amos | ATH | Olympics / Opening Flagbearer | 2012—2020 | 1–0–0 2013 Kazan ATH gold: 800 m | |
| Iryna Amshennikova | SWM | Olympics | 2004—2008 | 0–0–1 2005 İzmir SWI bronze: 100 m backstroke | |
| An Ba-Ul | JUD | Olympics | 2016—2024 | 2–1–0 2015 Gwangju JUD gold: half-lightweight -66 kg, silver: team; 2017 Taipei JUD gold: half-lightweight -66 kg | |
| An Chang-Rim | JUD | Olympics | 2016—2020 | 1–1–0 2015 Gwangju JUD gold: lightweight -73 kg, silver: team | |
| An Kum-Ae | JUD | Olympics | 2008—2012 | 0–1–1 2001 Beijing JUD bronze: half-lightweight -52 kg; 2003 Daegu JUD silver: half-lightweight -52 kg | |
| An Myong-Hwa | GAR | Olympics | 1992 | 1–1–1 1991 Sheffield GYM gold: team, silver: all-around, bronze: horse vault | |
| Galina Anahrieva | ROW | Olympics | 1988—1992 | 1–1–0 1987 Zagreb ROW silver: quadruple sculls; 1989 Duisburg ROW gold: quadruple sculls | |
| Takamasa Anai | JUD | Olympics | 2012 | 2–1–0 2003 Daegu JUD silver: team; 2007 Bangkok JUD gold: half-heavyweight -100 kg and team | |
| Akhmed Anarbayev | SWM | Olympics | 1968 | 0–2–0 1970 Torino SWI silver: 4×100 m freestyle relay and 4×200 m freestyle relay | |
| Émilie Andéol | JUD | Olympics | 2016 | 0–1–3 2007 Bangkok JUD silver: team; 2011 Shenzhen JUD bronze: heavyweight +78 kg, open class, and team | |
| Alyssa Anderson | SWM | Olympics | 2012 | 1–0–0 2011 Shenzhen SWI gold: 4×200 m freestyle relay (swam in heats only) | |
| Andrea Anderson | ATH | Olympics | 2000 | 1–0–0 1997 Catania ATH gold: 4×100 m relay | |
| Haley Anderson | OWS | Olympics | 2012—2020 | 1–1–0 2011 Shenzhen SWI gold: 1500 m freestyle, silver: 800 m freestyle | |
| Jodi Anderson | ATH | Olympics | 1984 | 0–1–1 1977 Sofia ATH bronze: long jump; 1979 Ciudad de México ATH silver: long jump | |
| Katie Anderson | ATH | Olympics | 1988—2000 | 0–0–1 1993 Buffalo ATH bronze: 4×100 m relay | |
| Wayne Anderson | SWM | Olympics | 1964 | 0–0–1 1965 Budapest SWI bronze: 200 m breaststroke | |
| Tord Andersson | DIV | Olympics | 1968 | 0–0–1 1967 Tokyo DIV bronze: 3 m springboard | |
| Kozue Ando | FBL | Olympics | 2004—2012 | 0–1–0 2003 Daegu FTB silver | |
| Lyudmila Andonova | ATH | Olympics | 1988—1992 | 0–1–0 1981 București ATH silver: high jump | |
| Alessandro Andrei | ATH | Olympics | 1984—1992 | 0–1–0 1985 Kobe ATH silver: shot put | |
| Vasile Andrei | WRE | Olympics / Opening Flagbearer | 1980—1988 | 0–1–0 1981 București WRE silver: Greco-Roman heavyweight -100 kg | |
| Enrique Andreu | BKB | Olympics | 1988—1992 | 0–0–1 1987 Zagreb BAS bronze | |
| Viktoriya Andreyeva | SWM | Olympics | 2012—2016 | 4–1–0 2013 Kazan SWI gold: 200 m freestyle, 200 m medley, 4×100 m freestyle relay, and 4×100 m medley relay, silver: 4×200 m freestyle relay | |
| Nikolay Andrianov | GAR | Olympics / Referee / Athlete Oath Taker | 1972—1992 | 4–1–0 1973 Moskva GYM gold: all-around, floor, pommelled horse, and team, silver: horse vault | |
| Dragan Andrić | WPO | Olympics / Coach | 1984—2012 | 0–0–1 1987 Zagreb WAP bronze | |
| Gheorghe Andriev | CSP | Olympics | 1988—1996 | 0–1–1 1987 Zagreb CAN silver: C2 500 m, bronze: C2 1000 m | |
| Spyros Andriopoulos | ATH | Olympics | 1996 | 0–1–0 1987 Zagreb ATH silver: 10000 m | |
| Vyacheslav Andrusenko | SWM | Olympics | 2016 | 0–0–1 2017 Taipei SWI bronze: 4×200 m freestyle relay | |
| Nedyalka Angelova | ATH | Olympics | 1972 | 0–1–0 1970 Torino ATH silver: pentathlon | |
| Gigel Anghel | WRE | Olympics | 1976 | 0–0–1 1977 Sofia WRE bronze: freestyle featherweight -62 kg | |
| Tatyana Anisimova | ATH | Olympics | 1976—1980 | 3–1–1 1975 Roma ATH gold: 4×100 m relay, bronze: 100 m hurdles; 1977 Sofia ATH gold: 4×100 m relay, silver: 100 m hurdles; 1979 Ciudad de México ATH gold: 4×100 m relay | |
| Emilia Ankiewicz | ATH | Olympics | 2016 | 0–1–0 2015 Gwangju ATH silver: 400 m hurdles | |
| Eddy Annijs | ATH | Olympics | 1984 | 0–1–0 1983 Edmonton ATH silver: high jump | |
| Noriko Anno | JUD | Olympics | 1996—2004 | 1–0–0 1995 Fukuoka JUD gold: open class | |
| Adrián Annus | ATH | Olympics | 1996—2004 | 0–0–1 2001 Beijing ATH bronze: hammer throw | |
| Helmut Anschütz | FEN | Olympics | 1960 | 0–0–1 1961 Sofia FEN bronze: épée team | |
| LaDonna Antoine | ATH | Olympics | 1996—2000 | 0–0–1 1997 Catania ATH bronze: 4×100 m relay | |
| Semyon Antonov | BKB | Olympics | 2012 | 1–0–0 2013 Kazan BAS gold | |
| Aleksandra Antonova | WPO | Olympics | 2012 | 1–0–1 2009 Beograd WAP bronze; 2013 Kazan WAP gold | |
| Diana Antonova | WPO | Olympics | 2012 | 1–0–1 2011 Shenzhen WAP bronze; 2013 Kazan WAP gold | |
| Jitka Antošová | ROW | Olympics | 2008—2012 | 0–1–0 2013 Kazan ROW silver: single sculls | |
| Oļegs Antropovs | VVO | Olympics | 1968 | 1–0–0 1973 Moskva VOL gold | |
| Yelena Anyushina | CSP | Olympics | 2016 | 0–1–0 2013 Kazan CAN silver: K4 500 m | |
| Shinji Aoto | ATH/BOB | Olympics | 1988—1998 | 0–0–1 1987 Zagreb ATH bronze: 4×100 m relay | |
| Saïd Aouita | ATH | Olympics / Non-starter | 1984—1992 | 1–0–0 1981 București ATH gold: 1500 m | |
| Ayari Aoyama | SWM | Olympics | 1996 | 0–0–1 2001 Beijing SWI bronze: 4×100 m freestyle relay | |
| Eşref Apak | ATH | Olympics | 2004—2020 | 0–1–0 2005 İzmir ATH silver: hammer throw | |
| Kiradech Aphibarnrat | GLF | Olympics | 2016—2024 | 1–0–0 2007 Bangkok GOL gold: team | |
| Vladimer Aptsiauri | FEN | Olympics | 1988 | 0–1–0 1981 București FEN silver: foil team | |
| Enrique Aquino | ATH | Olympics | 1980 | 0–1–1 1979 Ciudad de México ATH silver: 10000 m, bronze: 5000 m | |
| Toshiaki Araki | FEN | Olympics | 1964 | 1–0–1 1967 Tokyo FEN gold: foil team, bronze: épée team | |
| José Roberto Aranha | SWM | Olympics | 1968—1972 | 0–0–2 1973 Moskva SWI bronze: 4×100 m freestyle relay and 4×200 m freestyle relay | |
| Rômulo Arantes | SWM | Olympics | 1972—1980 | 1–1–2 1977 Sofia SWI gold: 100 m backstroke; 1979 Ciudad de México SWI silver: 100 m backstroke; 1981 București SWI bronze: 100 m backstroke and 4×100 m medley relay | |
| Franjo Arapović | BKB | Olympics | 1988—1992 | 1–0–0 1987 Zagreb BAS gold (competed for Yugoslavia) | |
| Anđelija Arbutina | BKB | Olympics | 1988 | 1–0–0 1987 Zagreb BAS gold | |
| José Arcega | BKB | Olympics | 1992 | 0–0–1 1987 Zagreb BAS bronze | |
| Angelo Arcidiacono | FEN | Olympics | 1976—1984 | 1–1–0 1977 Sofia FEN silver: sabre; 1981 București FEN gold: sabre team | |
| Giulia Arcioni | ATH | Olympics | 2008 | 1–0–0 2009 Beograd ATH gold: 4×100 m relay | |
| Suzana Ardeleanu | FEN | Olympics / Non-starter | 1972—1980 | 1–1–0 1970 Torino FEN silver: foil team; 1973 Moskva FEN gold: foil team | |
| Walter Arena | ATH | Olympics | 1992 | 1–0–0 1989 Duisburg ATH gold: 20 km walk | |
| Yordanis Arencibia | JUD | Olympics | 2000—2008 | 0–1–0 2003 Daegu JUD silver: half-lightweight -66 kg | |
| Helga Arendt | ATH | Olympics | 1988 | 0–1–0 1989 Duisburg ATH silver: 4×400 m relay | |
| Blanca Ares | BKB | Olympics | 1992 | 0–1–0 1991 Sheffield BAS silver | |
| Franco Arese | ATH | Olympics | 1968—1972 | 1–0–0 1970 Torino ATH gold: 1500 m | |
| Luis Felipe Areta | ATH | Olympics | 1960—1968 | 0–0–1 1963 Porto Alegre ATH bronze: triple jump | |
| Yosuke Arimitsu | DIV | Olympics | 1964—1968 | 1–0–0 1967 Tokyo DIV gold: platform | |
| Ramil Aritkulov | ATH | Olympics | 2004 | 0–1–0 2003 Daegu ATH silver: 800 m | |
| Vasily Arkhipenko | ATH | Olympics | 1980 | 0–1–0 1979 Ciudad de México ATH silver: 400 m hurdles | |
| Mihaela Armășescu | ROW | Olympics | 1984—1988 | 0–1–0 1987 Zagreb ROW silver: coxless pairs | |
| Marie-Thérèse Armentero | SWM | Olympics | 1984—1988 | 0–1–0 1987 Zagreb SWI silver: 50 m freestyle | |
| Daniel Arnamnart | SWM | Olympics | 2012 | 0–1–0 2013 Kazan SWI silver: 4×100 m freestyle relay | |
| Isabelle Arnould | SWM | Olympics | 1988—1992 | 0–1–1 1993 Buffalo SWI silver: 1500 m freestyle, bronze: 400 m freestyle | |
| Marco Arpino | FEN | Olympics | 1992—1996 | 1–1–1 1987 Zagreb FEN bronze: foil team; 1991 Sheffield FEN gold: foil team; 1993 Buffalo FEN silver: foil team | |
| Valentina Arrighetti | VVO | Olympics | 2012 | 1–0–0 2009 Beograd VOL gold | |
| Vladimir Artyomov | GAR | Olympics | 1988 | 3–3–2 1983 Edmonton GYM gold: team, silver: all-around, floor, and parallel bars; 1987 Zagreb GYM gold: parallel bars and team, bronze: all-around and horse vault | |
| Nataliya Artyomova | ATH | Olympics | 1988 | 0–0–1 1987 Zagreb ATH bronze: 3000 m | |
| Zorana Arunović | SHO | Olympics / Closing Flagbearer | 2012—2024 | 0–1–0 2011 Shenzhen SHO silver: 25 m sporting pistol | |
| Tatyana Aryasova | ATH | Olympics | 2008 | 0–1–0 2001 Beijing ATH silver: 5000 m (competed as Tatyana Khmeleva) | |
| Donaldo Arza | ATH | Olympics / Opening Flagbearer | 1972 | 0–0–1 1970 Torino ATH bronze: 800 m | |
| Vladimir Arzamaskov | BKB | Olympics | 1976 | 0–1–0 1973 Moskva BAS silver | |
| Yevgeny Arzhanov | ATH | Olympics | 1968—1972 | 1–0–0 1973 Moskva ATH gold: 800 m | |
| Shinobu Asagoe | TEN | Olympics | 2000—2004 | 1–0–1 1995 Fukuoka TEN gold: doubles; 1997 Catania TEN bronze: doubles | |
| Kentaro Asahi | VBV | Olympics | 2008—2012 | 0–1–0 1999 Palma de Mallorca VOL silver | |
| Kiyoshi Asai | ATH | Olympics | 1964 | 0–1–0 1961 Sofia ATH silver: 4×100 m relay | |
| Nugzar Asatiani | FEN | Olympics | 1960—1964 | 0–2–0 1961 Sofia FEN silver: sabre and sabre team | |
| Ali Ashkani | WRE | Olympics | 2000—2004 | 1–0–0 2005 İzmir WRE gold: Greco-Roman lightweight -60 kg | |
| Alina Astafei | ATH | Olympics | 1988—1996 | 1–0–0 1989 Duisburg ATH gold: high jump (competed as Galina Astafei for Romania) | |
| Ihar Astapkovich | ATH | Olympics / Opening Flagbearer | 1992—2004 | 2–0–0 1987 Zagreb ATH gold: hammer throw (competed for the Soviet Union); 1989 Duisburg ATH gold: hammer throw (competed for the Soviet Union) | |
| Vladimir Atamas | ATH | Olympics | 1972 | 0–1–0 1973 Moskva ATH silver: 4×100 m relay | |
| Atanaska Atanassova | ATH | Non-starter | 1980 | 0–1–0 1977 Sofia ATH silver: 4×100 m relay | |
| Sarah Atcho-Jaquier | ATH | Olympics | 2016—2024 | 1–0–0 2019 Napoli ATH gold: 4×100 m relay | |
| Angela Atede | ATH | Olympics | 1996—2000 | 1–0–0 1997 Catania ATH gold: 100 m hurdles | |
| Loïc Attely | FEN | Olympics | 2004 | 0–0–1 1999 Palma de Mallorca FEN bronze: foil team |