Host cities:
| Athlete | Nation(s) | Sport(s) | Role(s) | Era | Notes |
|---|---|---|---|---|---|
| Jatyr | BKB | Olympics | 1960—1964 | 1–0–0 1963 Porto Alegre BAS gold | |
| Daniela Jaworska | ATH | Olympics | 1968—1972 | 1–0–0 1970 Torino ATH gold: javelin throw | |
| Dorota Jędrusińska | ATH | Olympics | 2008 | 0–1–0 2009 Beograd ATH silver: 4×100 m relay | |
| Otylia Jędrzejczak | SWM | Olympics | 2000—2012 | 3–0–0 2005 İzmir SWI gold: 200 m freestyle, 100 m butterfly, and 200 m butterfly | |
| Jaime Jeffersón | ATH | Olympics | 1992—1996 | 2–0–0 1985 Kobe ATH gold: long jump; 1989 Duisburg ATH gold: long jump | |
| Thomas Jefferson | ATH | Olympics | 1984 | 0–0–1 1985 Kobe ATH bronze: 4×100 m relay | |
| Martin Jellinghaus | ATH | Olympics | 1968—1972 | 0–1–0 1970 Torino ATH silver: 400 m | |
| David Jenkins | ATH | Olympics | 1972—1980 | 0–1–1 1973 Moskva ATH silver: 4×400 m relay, bronze: 400 m | |
| Toby Jenkins | WPO | Olympics | 2004 | 0–0–1 2003 Daegu WAP bronze | |
| Shelly Jenneke | ATH | Olympics / YOG | 2010—2024 | 0–0–1 2015 Gwangju ATH bronze: 100 m hurdles | |
| Gary Jennings | ATH | Olympics | 1996 | 0–0–1 1995 Fukuoka ATH bronze: 4×400 m relay | |
| Terrence Jennings | TKW | Olympics | 2012 | 0–0–1 2009 Beograd TKW bronze: featherweight -67 kg | |
| Annemette Jensen | ATH | Olympics | 2004 | 0–0–1 1999 Palma de Mallorca ATH bronze: 10000 m | |
| Jeon Hui-Suk | FEN | Olympics | 2012—2020 | 0–1–1 2009 Beograd FEN bronze: foil team; 2011 Shenzhen FEN silver: foil | |
| Jeon Ji-Hui | TTE | Olympics | 2016—2024 | 4–0–3 2015 Gwangju TTN gold: mixed doubles, bronze: doubles and team; 2017 Taipei TTN gold: singles, mixed doubles, and team, bronze: doubles | |
| Jeong Bo-Gyeong | JUD | Olympics | 2016 | 1–2–1 2015 Gwangju JUD gold: extra-lightweight -48 kg, silver: team; 2017 Taipei JUD silver: team, bronze: extra-lightweight -48 kg | |
| Jeong Da-Un | JUD | Olympics | 2012 | 1–1–0 2009 Beograd JUD silver: team; 2013 Kazan JUD gold: team | |
| Jeong Dong-Ho | FBL | Non-starter | 2012 | 0–1–0 2015 Gwangju FTB silver | |
| Jeong Gil-Ok | FEN | Olympics | 2008—2012 | 0–1–1 2003 Daegu FEN silver: foil team, bronze: foil | |
| Jeong Gyeong-Mi | JUD | Olympics | 2008—2012 | 0–2–1 2009 Beograd JUD silver: half-heavyweight -78 kg and team; 2011 Shenzhen JUD bronze: half-heavyweight -78 kg | |
| Jeong Ji-Hyeon | WRE | Olympics | 2004—2012 | 0–1–0 2005 İzmir WRE silver: Greco-Roman welterweight -66 kg | |
| Jeong Jin-Su | GAR | Olympics | 1992—2000 | 1–2–1 1995 Fukuoka GYM gold: parallel bars, silver: all-around, bronze: floor; 1999 Palma de Mallorca GYM silver: parallel bars | |
| Jeong Seon-Yong | JUD | Olympics / Non-Medal | 1988—1996 | 1–0–1 1995 Fukuoka JUD gold: team, bronze: lightweight -56 kg | |
| Jeong Seong-Suk | JUD | Olympics | 1996—2000 | 2–0–0 1995 Fukuoka JUD gold: half-middleweight -61 kg and team | |
| Jeong Seul-Gi | SWM | Olympics | 2008 | 1–0–0 2007 Bangkok SWI gold: 200 m breaststroke | |
| Daniel Jérent | FEN | Olympics | 2016 | 1–0–0 2013 Kazan FEN gold: épée team | |
| Harry Jerome | ATH | Olympics | 1960—1968 | 0–0–1 1965 Budapest ATH bronze: 100 m | |
| Marta Jeschke | ATH | Olympics | 2008—2012 | 0–1–0 2009 Beograd ATH silver: 4×100 m relay | |
| Marko Jevtović | TTE | Olympics | 2012—2020 | 0–0–1 2009 Beograd TTN bronze: doubles | |
| Jaromír Ježek | JUD | Olympics | 2008—2016 | 0–0–1 2009 Beograd JUD bronze: half-middleweight -81 kg | |
| Zdravko Ježić | WPO | Olympics | 1952—1960 | 1–0–0 1959 Torino WAP gold | |
| Ji Kyong-Sun | JUD | Olympics | 2000 | 0–1–0 2003 Daegu JUD silver: half-middleweight -63 kg | |
| Ji Sang-Jun | SWM | Olympics | 1992—1996 | 1–0–1 1995 Fukuoka SWI gold: 200 m backstroke; 1997 Catania SWI bronze: 200 m backstroke | |
| Ji Wei | ATH | Olympics | 2008 | 0–1–0 2007 Bangkok ATH silver: 110 m hurdles | |
| Jiang Shuai | FBL | Non-starter | 2008 | 0–1–1 2003 Daegu FTB bronze; 2005 İzmir FTB silver | |
| Jiang Yuyuan | GAR | Olympics | 2008 | 3–2–0 2009 Beograd GYM gold: all-around, balance beam, and team, silver: floor and uneven bars | |
| Sutiya Jiewchaloemmit | SHO | Olympics | 2008—2020 | 0–1–0 2007 Bangkok SHO silver: skeet | |
| Iveri Jikurauli | JUD | Olympics | 2000—2004 | 0–0–1 1999 Palma de Mallorca JUD bronze: half-heavyweight -100 kg | |
| Anacleto Jiménez | ATH | Olympics | 1996 | 1–0–0 1987 Zagreb ATH gold: 5000 m | |
| Jin Jun-Taek | VVO | Olympics | 1972 | 0–0–1 1970 Torino VOL bronze | |
| Jin Ling | ATH | Olympics | 1988 | 0–0–1 1989 Duisburg ATH bronze: high jump | |
| Jin Xiaomei | FBL | Olympics | 2004 | 0–0–1 2003 Daegu FTB bronze | |
| Kenjiro Jitsui | ATH | Olympics | 1996 | 0–1–0 1991 Sheffield ATH silver: marathon | |
| Jo Bun-Hui | ATH | Olympics | 2004—2008 | 0–1–1 2003 Daegu ATH silver: half marathon; 2007 Bangkok ATH bronze: 10000 m | |
| Jo Eun-Ji | HOC | Non-starter | 2012 | 1–0–0 2013 Kazan HOK gold | |
| Jo Gu-Ham | JUD | Olympics | 2016—2020 | 2–2–0 2013 Kazan JUD gold: heavyweight +100 kg and team; 2015 Gwangju JUD gold: half-heavyweight -100 kg, silver: team | |
| Jo Hyeon-Ju | GAR | Olympics | 2008 | 1–0–0 2011 Shenzhen GYM gold: vault | |
| Jo In-Cheol | JUD | Olympics | 1996—2000 | 1–1–0 1995 Fukuoka JUD gold: team, silver: half-middleweight -78 kg | |
| Jo Jae-Hak | VVO | Olympics | 1976 | 0–0–1 1970 Torino VOL bronze | |
| Jo Jun-Ho | JUD | Olympics | 2012 | 1–0–0 2009 Beograd JUD gold: team | |
| Jo Min-Seon | JUD | Olympics / Non-Medal | 1988—2000 | 2–0–0 1995 Fukuoka JUD gold: middleweight -66 kg and team | |
| Jo Seong-Min | GAR | Olympics | 1996—2004 | 0–1–2 1997 Catania GYM silver: floor, bronze: horse vault; 1999 Palma de Mallorca GYM bronze: horse vault | |
| Jo Yeong-Gwang | GAR | YOG | 2010 | 0–1–0 2015 Gwangju GYM silver: team | |
| Michał Joachimowski | ATH | Olympics | 1972—1976 | 1–0–0 1975 Roma ATH gold: triple jump | |
| Anaso Jobodwana | ATH | Olympics / Closing Flagbearer | 2012—2020 | 2–0–0 2013 Kazan ATH gold: 100 m and 200 m | |
| Rafael Jofresa | BKB | Olympics | 1992 | 0–0–1 1987 Zagreb BAS bronze | |
| Thorsten Johansson | ATH | Olympics | 1976 | 0–0–1 1975 Roma ATH bronze: 200 m | |
| Brian Johns | SWM | Olympics | 2000—2008 | 1–1–2 2007 Bangkok SWI gold: 200 m medley, silver: 4×100 m freestyle relay, bronze: 200 m freestyle; 2009 Beograd SWI bronze: 4×200 m freestyle relay | |
| Ben Johnson | ATH | Olympics | 1984—1992 | 0–1–0 1983 Edmonton ATH silver: 4×100 m relay | |
| Dave Johnson | ATH | Olympics | 1988—1992 | 1–0–0 1989 Duisburg ATH gold: decathlon | |
| David Johnson | SWM | Olympics | 1968 | 3–0–0 1973 Moskva SWI gold: 100 m backstroke, 200 m backstroke, and 4×100 m medley relay | |
| Jenna Johnson | SWM | Olympics | 1984 | 1–1–0 1985 Kobe SWI gold: 4×100 m medley relay, silver: 100 m freestyle | |
| Lawrence Johnson | ATH | Olympics | 1996—2000 | 0–1–0 1995 Fukuoka ATH silver: pole vault | |
| Michael Johnson | ATH | Olympics | 1992—2000 | 0–1–0 1989 Duisburg ATH silver: 4×400 m relay | |
| Shannon Johnson | BKB | Olympics | 2004 | 1–0–0 1997 Catania BAS gold | |
| Abby Johnston | DIV | Olympics | 2012—2016 | 0–0–2 2009 Beograd DIV bronze: synchronized springboard and team | |
| Pascal Jolyot | FEN | Olympics | 1980—1984 | 0–1–0 1985 Kobe FEN silver: foil team | |
| Jon Hyon-Ju | DIV | Olympics | 2004 | 0–1–1 2003 Daegu DIV silver: synchronized platform, bronze: team | |
| Ildikó Jónás | ATH | Olympics | 1960 | 0–0–1 1965 Budapest ATH bronze: 4×100 m relay | |
| Carolyn Jones | BKB | Olympics | 1992 | 1–0–0 1991 Sheffield BAS gold | |
| Cullen Jones | SWM | Olympics | 2008—2012 | 1–0–0 2005 İzmir SWI gold: 50 m freestyle | |
| Diane Jones | ATH | Olympics | 1972—1976 | 0–0–1 1973 Moskva ATH bronze: pentathlon | |
| Esther Jones | ATH | Olympics | 1992 | 1–0–1 1989 Duisburg ATH gold: 4×100 m relay, bronze: 200 m | |
| Roddy Jones | SWM | Olympics | 1968 | 0–0–2 1967 Tokyo SWI bronze: 100 m backstroke and 4×100 m medley relay | |
| Jong Chun-Hui | WLF | YOG | 2014 | 0–0–1 2017 Taipei WLT bronze: light-heavyweight -69 kg | |
| Jong Yong-Ok | ATH | Olympics | 2000—2008 | 0–0–1 2007 Bangkok ATH bronze: half marathon | |
| Maneepong Jongjit | BDM | Olympics | 2012 | 1–0–2 2011 Shenzhen BDM gold: doubles, bronze: mixed doubles and team | |
| Stella Jongmans | ATH | Olympics | 1992—1996 | 1–0–0 1995 Fukuoka ATH gold: 800 m | |
| Abigél Joó | JUD | Olympics | 2012—2016 | 1–0–0 2013 Kazan JUD gold: half-heavyweight -78 kg | |
| Lars Jorgensen | SWM | Olympics | 1988 | 0–1–0 1993 Buffalo SWI silver: 800 m freestyle | |
| Frédérique Jossinet | JUD | Olympics | 2004—2008 | 1–0–2 1999 Palma de Mallorca JUD gold: team, bronze: extra-lightweight -48 kg; 2001 Beijing JUD bronze: extra-lightweight -48 kg | |
| Sergėjus Jovaiša | BKB | Olympics | 1980—1992 | 0–2–0 1977 Sofia BAS silver (competed for the Soviet Union); 1981 București BAS silver (competed for the Soviet Union) | |
| Stefan Jović | BKB | Olympics | 2016 | 0–0–1 2013 Kazan BAS bronze | |
| Bogna Jóźwiak | FEN | Olympics | 2008—2016 | 0–0–1 2005 İzmir FEN bronze: sabre team | |
| Jarosława Jóźwiakowska-Bieda | ATH | Olympics | 1960—1964 | 0–0–1 1959 Torino ATH bronze: high jump (competed as Jarosława Jóźwiakowska) | |
| Urszula Jóźwik | ATH | Olympics | 1968—1972 | 0–1–0 1973 Moskva ATH silver: 4×100 m relay | |
| Ju Hui | HBL | Olympics | 2012—2020 | 0–1–0 2015 Gwangju HAN silver | |
| Ju Se-Hyeok | TTE | Olympics | 2004—2016 | 0–1–1 2001 Beijing TTN silver: doubles, bronze: team | |
| Alberto Juantorena | ATH | Olympics | 1972—1980 | 2–0–0 1973 Moskva ATH gold: 400 m; 1977 Sofia ATH gold: 800 m | |
| Mirna Jukic | SWM | Olympics | 2004—2008 | 0–0–1 2007 Bangkok SWI bronze: 100 m breaststroke | |
| Arsen Julfalakyan | WRE | Olympics / Closing Flagbearer | 2008—2016 | 0–0–1 2013 Kazan WRE bronze: Greco-Roman middleweight -74 kg | |
| Ronald Julião | ATH | Olympics | 2012 | 1–0–1 2011 Shenzhen ATH bronze: discus throw; 2013 Kazan ATH gold: discus throw | |
| Leigh Julius | ATH | Olympics | 2004—2008 | 2–3–1 2003 Daegu ATH gold: 200 m, silver: 100 m; 2005 İzmir ATH gold: 200 m; 2007 Bangkok ATH silver: 200 m and 4×100 m relay; 2009 Beograd ATH bronze: 4×100 m relay | |
| Sherali Juraev | JUD | Olympics | 2016 | 0–1–0 2011 Shenzhen JUD silver: middleweight -90 kg | |
| Radek Juška | ATH | Olympics | 2016—2024 | 1–0–0 2017 Taipei ATH gold: long jump | |
| Vazha K'ach'arava | VVO | Olympics | 1964 | 1–0–0 1963 Porto Alegre VOL gold | |
| Teimuraz K'ak'ulia | TEN | Non-Medal | 1968 | 3–0–0 1973 Moskva TEN gold: singles, doubles, and mixed doubles | |
| Aleksandr Kabanov | WPO | Olympics / Coach | 1972—2012 | 2–0–0 1970 Torino WAP gold; 1973 Moskva WAP gold | |
| Lina Kačiušytė | SWM | Olympics | 1980 | 1–0–2 1981 București SWI gold: 200 m breaststroke, bronze: 100 m breaststroke, bronze: 4×100 m medley relay | |
| Jerzy Kaczmarek | FEN | Olympics | 1972 | 0–2–0 1970 Torino FEN silver: foil team; 1973 Moskva FEN silver: foil team | |
| Tomasz Kaczor | CSP | Olympics | 2012—2016 | 0–0–2 2013 Kazan CAN bronze: C2 500 m and C2 1000 m | |
| Oleksandr Kaidash | ATH | Olympics | 2000 | 0–1–0 2001 Beijing ATH silver: 4×400 m relay | |
| Natasha Kaiser-Brown | ATH | Olympics | 1992 | 1–0–0 1989 Duisburg ATH gold: 4×400 m relay | |
| Masaki Kaito | VVO | Olympics | 1988 | 1–0–0 1985 Kobe VOL gold | |
| Hiroshi Kajiyama | GAR | Olympics | 1976 | 2–6–1 1973 Moskva GYM silver: floor, pommelled horse, and team; 1977 Sofia GYM gold: all-around and floor, silver: parallel bars, horizontal bar, and team, bronze: pommelled horse | |
| Siarhei Kalamoyets | ATH | Olympics | 2016 | 0–0–1 2015 Gwangju ATH bronze: hammer throw | |
| Valter Kalaus | SWM | Olympics | 1988 | 0–0–1 1993 Buffalo SWI bronze: 400 m freestyle | |
| Murat Kalikulov | JUD | Olympics | 2004 | 0–1–0 2001 Beijing JUD silver: half-lightweight -66 kg | |
| Nikola Kalinić | BKB | Olympics | 2016 | 0–0–1 2013 Kazan BAS bronze | |
| Irina Kalinina | DIV | Olympics | 1976—1980 | 3–1–0 1977 Sofia DIV gold: 3 m springboard and platform; 1979 Ciudad de México DIV gold: 3 m springboard, silver: platform | |
| Volodymyr Kaliuzhnyi | FEN | Olympics | 1996—2004 | 0–0–2 1991 Sheffield FEN bronze: sabre team (competed for the Soviet Union); 1997 Catania FEN bronze: sabre team | |
| János Kalmár | FEN | Olympics / Referee | 1968—1984 | 1–0–0 1965 Budapest FEN gold: sabre team | |
| Mantas Kalnietis | BKB | Olympics | 2012—2016 | 1–0–0 2007 Bangkok BAS gold | |
| Henrik Kalocsai | ATH | Olympics | 1964—1968 | 1–0–0 1965 Budapest ATH gold: triple jump | |
| Athanasios Kalogiannis | ATH | Olympics / Torch Bearer | 1984—1992 | 0–1–0 1987 Zagreb ATH silver: 400 m hurdles | |
| Lesia Kalytovska | CTR | Olympics | 2008—2012 | 1–1–0 2011 Shenzhen CYC gold: points race, silver: 3000 m individual pursuit | |
| Bayano Kamani | ATH | Olympics / Closing Flagbearer | 2004—2008 | 0–1–0 1999 Palma de Mallorca ATH silver: 400 m hurdles (competed for the United States) | |
| Naoko Kamata | SAL | Olympics | 2008 | 0–1–0 2005 İzmir SAI silver: 470 women | |
| Sergey Kamensky | SHO | Olympics | 2016—2020 | 1–1–3 2011 Shenzhen SHO bronze: 50 m rifle three positions and 50 m rifle three positions team; 2013 Kazan SHO gold: 50 m rifle prone, silver: 10 m air rifle team, bronze: 50 m rifle prone team | |
| Valentina Kamenyok-Vinogradova | VVO | Olympics | 1964—1968 | 1–0–0 1965 Budapest VOL gold (competed as Valentina Vinogradova) | |
| Daiki Kamikawa | JUD | Olympics | 2012 | 0–1–1 2009 Beograd JUD silver: heavyweight +100 kg, bronze: team | |
| Mateusz Kamiński | CSP | Olympics | 2016—2020 | 0–0–1 2013 Kazan CAN bronze: C4 1000 m | |
| Yuya Kamoto | GAR | YOG | 2010 | 2–1–1 2015 Gwangju GYM gold: team, silver: parallel bars, bronze: horizontal bar; 2017 Taipei GYM gold: team | |
| Maria Kamrowska | ATH | Olympics | 1992 | 0–0–1 1991 Sheffield ATH bronze: heptathlon | |
| Berber Kamstra | SWM | Olympics | 1976 | 0–1–1 1979 Ciudad de México SWI silver: 4×100 m freestyle relay, bronze: 4×100 m medley relay relay | |
| Jenő Kamuti | FEN | Olympics / Referee / Administrator / Opening Flagbearer | 1960—2000 | 4–3–0 1959 Torino FEN silver: foil team; 1961 Sofia FEN gold: foil and foil team; 1963 Porto Alegre FEN gold: foil, silver: foil team and épée team; 1965 Budapest FEN gold: foil | |
| László Kamuti | FEN | Olympics | 1960—1972 | 1–1–0 1961 Sofia FEN gold: foil team; 1963 Porto Alegre FEN silver: foil team | |
| Andrei Kan | GAR | Olympics | 1996 | 2–0–0 1991 Sheffield GYM gold: parallel bars and team (competed for the Soviet Union) | |
| Masayoshi Kan | ATH | Olympics | 1992 | 0–1–0 1993 Buffalo ATH silver: 4×400 m relay | |
| Yevgeniya Kanayeva | GRY | Olympics | 2008—2012 | 9–1–0 2009 Beograd RGY gold: individual, ball, hoop, ribbon, and robe; 2011 Shenzhen RGY gold: individual, ball, clubs, and hoop, silver: ribbon | |
| Yoko Kando | SWM | Olympics | 1992 | 2–2–0 1993 Buffalo SWI gold: 100 m butterfly and 200 m butterfly, silver: 4×100 m medley relay; 1995 Fukuoka SWI silver: 4×100 m medley relay (swam in heats only) | |
| Mitsuko Kandori | GAR | Olympics | 1968 | 0–1–0 1967 Tokyo GYM silver: all-around | |
| Kazuya Kaneda | SWM | Olympics | 2012 | 0–1–0 2009 Beograd SWI silver: 200 m butterfly | |
| Yuzo Kanemaru | ATH | Olympics | 2008—2016 | 1–0–1 2009 Beograd ATH gold: 400 m, bronze: 4×400 m relay | |
| Rie Kaneto | SWM | Olympics | 2008—2016 | 1–1–0 2007 Bangkok SWI silver: 200 m breaststroke; 2009 Beograd SWI gold: 200 m breaststroke | |
| Shunsuke Kaneto | DIV | Olympics | 1960—1964 | 3–0–0 1961 Sofia DIV gold: 3 m springboard; 1963 Porto Alegre DIV gold: 3 m springboard and platform | |
| Kang Yun-Mi | GAR | Olympics | 2004 | 0–1–0 2005 İzmir GYM silver: team | |
| Tibor Kangyal | BKB | Olympics | 1964 | 0–0–1 1965 Budapest BAS bronze | |
| Miyuki Kano | VVO | Olympics | 2008 | 0–0–1 1997 Catania VOL bronze | |
| Gerd Kanter | ATH | Olympics / Closing Flagbearer | 2004—2016 | 1–0–0 2005 İzmir ATH gold: discus throw | |
| Andrey Kapralov | SWM | Olympics | 2000—2008 | 2–3–1 2003 Daegu SWI gold: 100 m freestyle and 4×200 m freestyle relay, silver: 4×100 m medley relay, bronze: 50 m freestyle; 2005 İzmir SWI silver: 50 m freestyle and 100 m freestyle | |
| Olga Kapranova | GRY | Olympics | 2008 | 0–3–0 2007 Bangkok RGY silver: individual, hoop, and ribbon | |
| Velik Kapsazov | GAR | Olympics | 1956—1964 | 0–0–1 1961 Sofia GYM bronze: all-around | |
| Mehmet Serhat Karadağ | WRE | Olympics | 1984 | 0–0–1 1977 Sofia WRE bronze: Greco-Roman flyweight -52 kg | |
| Nagihan Karadere | ATH | Olympics | 2012 | 0–1–1 2011 Shenzhen ATH silver: 4×400 m relay, bronze: 400 m hurdles | |
| Ashot Karagyan | FEN | Olympics | 1980 | 1–0–0 1973 Moskva FEN gold: épée team | |
| Yousef Karami | TKW | Olympics | 2004—2012 | 1–0–0 2007 Bangkok TKW gold: middleweight -84 kg | |
| Andranik Karapetyan | WLF | Olympics | 2016—2024 | 0–1–0 2017 Taipei WLT silver: light-heavyweight -85 kg | |
| Mariya Karashka | GAR | Olympics | 1968 | 0–0–1 1965 Budapest GYM bronze: team | |
| Nikolay Karasyov | ATH | Olympics | 1964 | 0–1–0 1965 Budapest ATH silver: shot put | |
| Branislav Karaulić | ATH | Olympics | 1988 | 0–1–0 1987 Zagreb ATH silver: 4×400 m relay | |
| Elvina Karimova | WPO | Olympics | 2016—2020 | 1–0–0 2013 Kazan WAP gold | |
| Dmytro Kariuchenko | FEN | Olympics | 2004—2016 | 3–0–0 2003 Daegu FEN gold: épée team; 2005 İzmir FEN gold: épée team; 2007 Bangkok FEN gold: épée team | |
| Julius Kariuki | ATH | Olympics | 1984—1988 | 1–0–0 1989 Duisburg ATH gold: 10000 m | |
| Kris Karlson | ROW | Olympics | 1992 | 0–0–1 1987 Zagreb ROW bronze: lightweight single sculls | |
| Raycho Karmadzhiev | CSP | Olympics | 1980 | 0–0–1 1987 Zagreb CAN bronze: C1 500 m | |
| Anna Karnaukh | WPO | Olympics | 2012—2020 | 1–0–0 2013 Kazan WAP gold | |
| György Kárpáti | SWM/WPO | Olympics / Non-starter | 1952—1964 | 1–1–2 1961 Sofia SWI bronze: 4×100 m freestyle relay and WAP bronze, 1963 Porto Alegre WAP gold, SWI silver: 4×100 m freestyle relay | |
| Viktoriya Karpenko | GAR | Olympics | 2000 | 0–1–1 1999 Palma de Mallorca GYM silver: team, bronze: uneven bars | |
| Svetlana Karpeyeva | SWM | Olympics | 2008 | 0–0–3 2007 Bangkok SWI bronze: 200 m medley; 2009 Beograd SWI bronze: 400 m medley and 4×100 m medley relay | |
| Yelena Karpova | BKB | Olympics | 2004 | 0–0–1 1999 Palma de Mallorca BAS bronze | |
| Oleksandra Karpovich | WPO | Olympics | 2008 | 0–0–2 2009 Beograd WAP bronze; 2011 Shenzhen WAP bronze | |
| Kateryna Karsak | ATH | Olympics | 2008—2012 | 0–0–1 2009 Beograd ATH bronze: discus throw | |
| Michael Karst | ATH | Olympics | 1976 | 1–2–0 1973 Moskva ATH silver: 3000 m steeplechase; 1975 Roma ATH silver: 3000 m steeplechase; 1977 Sofia ATH gold: 3000 m steeplechase | |
| Yuji Kasama | VVO | Olympics | 1988 | 0–0–1 1981 București VOL bronze | |
| Akihiro Kasamatsu | GAR | Olympics / Referee | 2000—2020 | 1–0–1 1999 Palma de Mallorca GYM gold: team, bronze: floor | |
| Indrek Kaseorg | ATH | Olympics | 1996—2000 | 0–1–0 1993 Buffalo ATH silver: decathlon | |
| Takehiro Kashima | GAR | Olympics | 2004—2008 | 2–0–1 2005 İzmir GYM gold: parallel bars and team, bronze: all-around | |
| Yury Kashirin | CRD | Olympics | 1980 | 1–0–0 1983 Edmonton CYC gold: team time trial | |
| Tatyana Kashirina | WLF | Olympics | 2012 | 1–0–0 2013 Kazan WLT gold: super-heavyweight +75 kg | |
| Igor Kashkarov | ATH | Olympics | 1956 | 0–1–0 1961 Sofia ATH silver: high jump | |
| Inna Kashyna | ATH | Olympics | 2016 | 2–0–0 2017 Taipei ATH gold: 20 km walk and 20 km walk team | |
| Orsolya Kasó | WPO | Olympics | 2016 | 0–1–0 2009 Beograd WAP silver | |
| Šárka Kašpárková | ATH | Olympics | 1992—2004 | 1–1–0 1993 Buffalo ATH silver: triple jump (competed for the Czech Republic); 1995 Fukuoka ATH gold: triple jump (competed for the Czech Republic) | |
| Romy Kasper | CRD | Olympics | 2016 | 0–0–1 2011 Shenzhen CYC bronze: road time trial team | |
| Dzmitry Kaspiarovich | GAR | Olympics | 2008—2012 | 0–0–1 2001 Beijing GYM bronze: floor | |
| Aurore Kassambara | ATH | Non-starter | 2008 | 0–2–0 2003 Daegu ATH silver: 4×100 m relay; 2005 İzmir ATH silver: 4×100 m relay | |
| Kyoko Kasuya | SWM | Olympics | 1992 | 0–0–1 1995 Fukuoka SWI bronze: 200 m breaststroke | |
| Renata Katewicz | ATH | Olympics | 1988—1996 | 1–0–0 1993 Buffalo ATH gold: discus throw | |
| Izumi Kato | SWM | Olympics | 2012 | 1–0–0 2011 Shenzhen SWI gold: 200 m medley | |
| Nobuya Kato | ATH | Olympics | 2016 | 0–1–0 2015 Gwangju ATH silver: 4×400 m relay | |
| Ryohei Kato | GAR | Olympics | 2012—2016 | 1–0–2 2013 Kazan GYM gold: floor, bronze: horizontal bar and team | |
| Sawao Kato | GAR | Olympics / Referee | 1968—2004 | 1–0–1 1967 Tokyo GYM gold: team, bronze: all-around | |
| Takeshi Kato | GAR | Olympics | 1968 | 2–2–0 1963 Porto Alegre GYM gold: team, silver: all-around; 1967 Tokyo GYM gold: team, silver: all-around | |
| Yuka Kato | SWM | Olympics | 2008—2012 | 1–1–0 2007 Bangkok SWI gold: 4×100 m medley relay, silver: 50 m butterfly | |
| András Katona | WPO | Olympics | 1960 | 2–2–2 1959 Torino SWI silver: 4×200 m freestyle relay and WAP silver; 1961 Sofia SWI bronze: 4×100 m freestyle relay and WAP bronze; 1963 Pôrto Alegre WAP gold; 1965 Budapest WAP gold | |
| József Katona | SWM | Olympics | 1960—1964 | 0–0–1 1965 Budapest SWI bronze: 400 m freestyle | |
| István Kausz | FEN | Olympics | 1960—1964 | 1–0–1 1959 Torino FEN gold: épée, bronze: épée team | |
| Christian Kauter | FEN | Olympics / Opening Flagbearer | 1968—1976 | 1–0–0 1967 Tokyo FEN gold: épée team | |
| Fabian Kauter | FEN | Olympics | 2012—2016 | 1–0–2 2007 Bangkok FEN bronze: épée team; 2009 Beograd FEN gold: épée team, bronze: épée | |
| Antanas Kavaliauskas | BKB | Olympics | 2012—2016 | 1–0–0 2007 Bangkok BAS gold | |
| Shingo Kawabata | ATH | Olympics | 2000 | 1–0–0 2001 Beijing ATH gold: 4×100 m relay | |
| Shunichi Kawai | VVO | Olympics | 1984—1988 | 1–0–1 1981 București VOL bronze; 1985 Kobe VOL gold | |
| Yukari Kawamoto | GRY | Olympics | 1992 | 0–2–0 1991 Sheffield RGY silver: hoop and rope | |
| Zygmunt Kawecki | FEN | Olympics | 1968—1972 | 0–0–1 1965 Budapest FEN bronze: sabre team | |
| Özlem Kaya | ATH | Olympics | 2012—2016 | 0–0–2 2015 Gwangju ATH bronze: 3000 m steeplechase; 2017 Taipei ATH bronze: 3000 m steeplechase | |
| Rıza Kayaalp | WRE | Olympics / Opening Flagbearer | 2008—2020 | 1–0–0 2013 Kazan WRE gold: Greco-Roman super-heavyweight -120 kg | |
| Oliver Kayser | FEN | Olympics | 2000 | 0–0–1 1999 Palma de Mallorca FEN bronze: épée team | |
| Hanna Kazak | ATH | Olympics / Non-starter | 1996—2008 | 0–0–1 2001 Beijing ATH bronze: 4×400 m relay | |
| Tatyana Kazankina | ATH | Olympics | 1976—1980 | 0–1–0 1977 Sofia ATH silver: 800 m |