Japan participated at the 2018 Summer Youth Olympics in Buenos Aires, Argentina from 6 October to 18 October 2018. Japan competes in 23 events and brought home 39 medals. It was the rehearsal of the hosting Summer Olympics as Tokyo was the host of the 2020 games which was held from 23 July to 8 August 2021.
Medalists
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Medal Name Sport Event Date Yuka Ueno Fencing Girls' foil 7 Oct Ramu Kawai Dancesport B-Girls' 8 Oct Keita Dohi Sport climbing Boys' combined 10 Oct Yu Hanaguruma Swimming Boys' 200 m breaststroke 10 Oct Takeru Kitazono Gymnastics Boys' individual all-around 11 Oct Wataru Sasaki Wrestling Boys' Greco-Roman 51 kg 12 Oct Shiori Asaba Swimming Girls' 200 m breaststroke 12 Oct Takeru Kitazono Gymnastics Boys' floor 13 Oct Nonoka Ozaki Wrestling Girls' freestyle 57 kg 13 Oct Yuki NaitoNaoki Tajima Tennis Mixed doubles 14 Oct Takeru Kitazono Gymnastics Boys' rings 14 Oct Takeru Kitazono Gymnastics Boys' parallel bars 15 Oct Takeru Kitazono Gymnastics Boys' horizontal bar 15 Oct Haruto Deguchi Athletics Boys' 400 m hurdles 16 Ovt Kokoro Sakaji Karate Girls' 59 kg 17 Oct Shuta Tanaka Sport climbing Boys' combined 10 Oct Miu Hirano Table tennis Girls' singles 10 Oct Tomokazu Harimoto Table tennis Boys' singles 10 Oct Keisuke Yoshida Swimming Boys' 800 m freestyle 11 Oct Mayuka Yamamoto Swimming Girls' 50 m freestyle 12 Oct Yuki NaitoNaho Sato Tennis Girls' doubles 13 Oct Miu HiranoTomokazu Harimoto Table tennis Mixed team 15 Oct Kazuki Furusawa Athletics Boys' pole vault 16 Oct Masaki Yamaoka Karate Boys' 61 kg 17 Oct Rinka Tahata Karate Girls' 53 kg 17 Oct Mai MiyamotoSara OinoYuria SutohRinka YokoyamaIchika AraiAki IkeuchiMiu MaedaMitsuki KobayashiRikako YamakawaMirano Abe Futsal Girls' tournament 17 Oct Sakura Sawashima Karate Girls' 59 kg 18 Oct Keisuke Yoshida Swimming Boys' 400 m freestyle 7 Oct Shigeyuki Nakarai Dancesport B-Boys' 8 Oct Taku Taniguchi Swimming Boys' 100 m breaststroke 8 Oct Kanami TannoYuma Oshimo Cycling Mixed BMX freestyle park 11 Oct Miku KojimaMayuka YamamotoNagisa IkemotoShiori Asaba Swimming Girls' 4 × 100 m medley relay 11 Oct Kodai Naraoka Badminton Boys' singles 12 Oct Shu Yamada Wrestling Boys' Greco-Roman 71 kg 12 Oct Miku KojimaTaku TaniguchIShinnosuke IshikawaNagisa Ikemoto Swimming Mixed 4 × 100 m medley relay 12 Oct Yuka Kagami Wrestling Girls' freestyle 73 kg 13 Oct Koki Wada Athletics Boys' long jump 15 Oct Seiryo Ikeda Athletics Boys' 100 m 15 Oct Rugby sevens Boys' tournament 15 Oct | style="text-align:left; width:22%; vertical-align:top;"|
Medals by sportSport TotalGymnastics 5 0 0 5Swimming 2 2 4 8Wrestling 2 0 2 4Karate 1 3 0 4Athletics 1 1 2 4Sport climbing 1 1 0 2Tennis 1 1 0 2Dancesport 1 0 1 2Fencing 1 0 0 1Table tennis 0 3 0 3Futsal 0 1 0 1Badminton 0 0 1 1Cycling 0 0 1 1Rugby sevens 0 0 1 1Total 15 12 12 39
Competitors Sport Boy Girl TotalArchery 1 1 2Athletics 8 6 14Badminton 1 1 2Cycling 2 2 4Dancesport 1 1 2Fencing 2 1 3Futsal – 10 10Golf 1 1 2Gymnastics 2 3 5Karate 3 3 6Modern pentathlon 0 1 1Rowing 1 0 1Rugby sevens 12 – 12 Sailing 1 0 1 Shooting 0 1 1 Sport climbing 2 1 3Swimming 4 4 8 Table tennis 1 1 2 Taekwondo 1 0 1Tennis 1 2 3Triathlon 1 1 2Weightlifting 0 1 1 Wrestling 3 2 5 Total 48 43 91
Archery Japan qualified two archers based on its performance at the 2017 World Archery Youth Championships.
Individual AthleteEventRanking roundRound of 32Round of 16QuarterfinalsSemifinalsFinal / RankScoreSeedOppositionScoreOppositionScoreOppositionScoreOppositionScoreOppositionScoreTetsuya AoshimaBoys' Individual65422L 5–6did not advance17Ruka UeharaGirls' Individual6672L 5–6did not advance17
Team AthletesEventRanking roundRound of 32Round of 16QuarterfinalsSemifinalsFinal / RankScoreSeedOppositionScoreOppositionScoreOppositionScoreOppositionScoreOppositionScore Mixed team129919L 4–5did not advance 17 127330L 4–5did not advance 17
Athletics
Boys Track & road events AthleteEventStage 1Stage 2TotalTimeRankTimeRankTimeRankSeiryo Ikeda100 m10.82310.30321.12Kosuke Ishida1500 m3:57.251111:525167Rintaro Kajiyama3000 m8:22.15512:108136Haruto Deguchi400 m hurdles51.40151.2811:42.68Yusuke Iwakawa5000 m walk21:49.401023:20.841245:10.24 12
Field Events AthleteEventStage 1Stage 2TotalTimeRankTimeRankTimeRankKazuki FurusawaPole vault5.1035.22210.32Koki WadaLong jump7.4647.66315.12Kentaro NakamuraJavelin throw66.311364.5512130.8612
Girls Track & road events AthleteEventStage 1Stage 2TotalTimeRankTimeRankTimeRankTakako Niisaka100 m12.22711.65823.878Maki Ueda800 m2:09.9182:10.0654:19.977Yuki Kanemitsu1500 m4:24.41413:13374Miyaka Sugata3000 m9:21.16513:5911169
Field Events AthleteEventStage 1Stage 2TotalTimeRankTimeRankTimeRankAzuki NakatsugawaLong jump5.8666.14512.005Yuika NakamuraJavelin throw43.6214DNS - - - Cross Country
Badminton
Japan qualified two players based on the Badminton Junior World Rankings.
Singles AthleteEventGroup StageQuarterfinalSemifinalFinal / OppositionScoreOppositionScoreOppositionScoreRankOppositionScoreOppositionScoreOppositionScoreRankKodai NaraokaBoys' singlesW (21–7, 21–5)W (21–8, 21–13)W (21–9, 21–12)1 QW (21–11, 21–11)L (21–14, 15–21, 22–24)W (21–17, 24–26, 22–20)Hirari MizuiGirls' singlesW (21–14, 21–16)W (21–1, 21–9)L (10–21, 21–17, 16–21)2did not advance9
Team AthleteEventGroup stageQuarterfinalSemifinalFinal / RankOppositionScoreOppositionScoreOppositionScoreRankOppositionScoreOppositionScoreOppositionScoreTeam Theta Mixed TeamsL (100–110)L (100–110)L (107–110)4QW (110–93)L (90–110)W (110–107)
Cycling
Japan qualified a boys' and girls' combined team based on its ranking in the Youth Olympic Games Junior Nation Rankings. They also qualified a mixed BMX racing team based on its ranking in the Youth Olympic Games BMX Junior Nation Rankings and two athletes in BMX freestyle based on its performance at the 2018 Urban Cycling World Championship.
Boys' combined team – 1 team of 2 athletes Girls' combined team – 1 team of 2 athletes Mixed BMX racing team – 1 team of 2 athletes Mixed BMX freestyle – 1 boy and 1 girl
Dancesport
Japan qualified two dancers based on its performance at the 2018 World Youth Breaking Championship.
B-Boys – Shigekix B-Girls – Ram
Fencing
Japan qualified three athletes based on its performance at the 2018 Cadet World Championship.
AthleteEventGroup StageRound of 16Quarterfinals Semifinals Final / / OppositionScoreOppositionScoreOppositionScoreOppositionScoreOppositionScoreOppositionScoreRankOppositionScoreOppositionScoreOppositionScoreOppositionScoreRankSeiya AsamiBoys' épéeW (5–1)L (3–4)L (2–5)W (5–3)W (5–1) 2 L (1–5)Did not advance6Hibiki KatoBoys' sabreL (1–5)W (5–1)W (5–1)L (4–5)L (3–5) 4W (15–9)L (12–15)Did not advance8Yuka UenoGirls' foilW (5–0)W (5–3)W (5–1)W (5–1)W (5–0)W (5–1)1 W (13–3)W (8–4)W (15–12)
Futsal
Girls Summary TeamEventGroup StageSemifinalFinal / OppositionscoreOppositionscoreOppositionscoreOppositionscoreRankOppositionscoreOppositionscoreRankJapanGirls' tournamentW 6–2W 4–1W 6–2L 0–22W 3–2L 1–4 Group D
Semi-finals
Finals
Golf
Individual AthleteEventRound 1Round 2Round 3TotalScoreRankScoreTotal RankScoreTotal RankScoreParRankKagetsu TsuruseGirls' Individual79 (+9)2277 (+7)1561979 (+9)23528235 +25 27Ryou HitsatsuneBoys' Individual75 (+5)2068 (-2)143170 (0)2134213 +3 5
Team AthletesEventRound 1(Fourball)Round 2(Foursome)Round 3(Individual Stroke)TotalScoreRankScoreRankGirlBoyTotal RankScoreParRankKagetsu TsuruseRyou HitsatsuneMixed team64 (-6)674 (+4)1576 70146 (+6) 11284 +4 9
Gymnastics
Artistic Japan qualified two gymnasts based on its performance at the 2018 Asian Junior Championship.
AthleteEventApparatusTotalRankTakeru KitazonoQualification13.50014.13313.70014.10014.26613.60083.2991 QAll-around13.83313.96613.46614.23313.00013.80083.299Floorcolspan=6 rowspan=5 13.633Parallel bars12.6666Rings13.533Parallel bars14.166Horizontal bar13.566
AthleteEventApparatusTotalRankChiharu YamadaQualification13.1009.73311.16612.56646.56521 Floorcolspan=4 12.0006
Rhythmic Japan qualified one gymnast based on its performance at the 2018 Asian Junior Championship.
Individual AthleteEventQualificationFinalHoopBallClubsRibbonTotalRankHoopBallClubsRibbonTotalRankAino YamadaIndividual14.90014.85015.45014.25059.4506 Q15.50015.30015.00012.40058.2008
Trampoline Japan qualified two gymnasts based on its performance at the 2018 Asian Junior Championship.
Boys' trampoline – 1 quota Girls' trampoline – 1 quota AthleteEventQualificationFinalRoutine 1Routine 2TotalRankScoreRankTakumi FujimotoBoys50.97512Did not advanceYuki OkunoGirls42.44050.39592.8356 Q50.7605
Karate
Japan qualified three athlete based on the rankings in the Buenos Aires 2018 Olympic Standings. Later, they qualified three more athletes based on its performance at one of the Karate Qualification Tournaments.
AthleteEventGroup StageSemifinal Final / OppositionScoreOppositionScoreOppositionScoreRankOppositionScoreOppositionScoreRankMasaki YamaokaBoys' 61 kgW (4–0)W (5–0)D (0–0)1W (8–0)L (0–8)Kotaro NakamuraBoys' 68 kgL (2–8)L (0–3)D (0–0)3Did not advanceKeisei SakiyamaBoys' +68 kgW (1–0)W (2–0)L (1–2)3Did not advanceRinka TahataGirls' 53 kgD (3–3)W (2–0)W (1–0)1W (2–0)L (1–2)Kokoro SakajiGirls' 59 kgW (4–0)W (1–0)W (1–0)1D (0–0)W (3–0)Sakura SawashimaGirls' +59 kgW (2–0)L (1–5)W (3–0)1W (9–1)L (0–3)
Modern pentathlon
Rowing
Japan qualified one boat based on its performance at the 2018 Asian Youth Olympic Games Qualification Regatta.
Boys' single sculls – 1 athlete
Rugby sevens
Boys' tournament
Summary TeamEventGroup StageBronze medal gameOppositionscoreOppositionscoreOppositionscoreOppositionscoreOppositionscoreRankOppositionscoreRankJapanBoys' tournamentW 14–12L 0–45W 29–0D 17–17L 14–293W 28–5
Group Stage
Bronze medal match
Sailing
Japan qualified one boat based on its performance at the 2018 Singapore Open (Asian Techno 293+ Qualifiers).
Boys' Techno 293+ – 1 boat
Shooting
Girls Rifle – Aoi Takagi
Individual AthleteEventQualificationFinalPointsRankPointsRankAoi TakagiGirls' 10m air rifle615.115did not advance
Team AthletesEventQualificationRound of 16QuarterfinalsSemifinalsFinal / PointsRankOppositionResultOppositionResultOppositionResultOppositionResultRankMixed 10 metre air rifle825.17 QL 7–10did not advance
Sport climbing
Japan qualified two sport climbers based on its performance at the 2017 World Youth Sport Climbing Championships. They also qualified a female climber based on its performance at the 2017 Asian Youth Sport Climbing Championships.
Boys' combined – 2 quotas (Keita Dohi, Shuta Tanaka) Girls' combined – 1 quota (Mao Nakamura)
Swimming
Boys AthleteEventHeatSemifinalFinalTimeRankTimeRankTimeRankKeisuke Yoshida200 m freestyle1:48.97 1 Qcolspan=2 1:48.755400 m freestyle3:51.68 1 Qcolspan=2 3:48.68800 m freestylecolspan=4 7:53.85Taku Taniguchi50 m breaststroke28.283 Q28.22428.204100 m breaststroke1:01.683 Q1:02.085 Q1:01.40200 m breaststroke2:16.678 Qcolspan=2 2:15.215 Yu Hanaguruma50 m breaststroke29.1816 Q29.0114Did not advance100 m breaststroke1:02.224 Q1:01.994 Q1:01.624200 m breaststroke2:13.581 Qcolspan=2 2:11.63Shinnosuke Ishikawa50 m butterfly24.6416 Q24.7614Did not advance100 m butterfly53.577 Q52.674 Q52.524200 m butterfly2:01.477 Qcolspan=2 1:59.426Keisuke YoshidaTaku TaniguchiShinnosuke IshikawaYu Hanaguruma4 × 100 m freestyle relaycolspan=4 3:26.806Keisuke YoshidaYu HanagurumaShinnosuke IshikawaTaku Taniguchi4 × 100 m medley relay3:45.343 Qcolspan=2 DSQ
Girls