Japan competed at the 1984 Summer Olympics in Los Angeles, United States. Japan returned to the Games after participating in the American-led boycott of the 1980 Summer Olympics. 226 competitors, 174 men and 52 women, took part in 147 events in 22 sports.
Medalists
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Archery
In their third Olympic archery competition, Japan won a bronze medal in the men's division as well as having a fourth place competitor in each division.
Women's Individual Competition: Hiroko Ishizu – 2525 points (4th place) Minako Hokari – 2481 points (10th place)
Men's Individual Competition: Hiroshi Yamamoto – 2563 points (Bronze Medal) Takayoshi Matsushita – 2552 points (4th place) Ichiro Shimamura – 2312 points (52nd place)
Athletics
Men's 400 metres
Susumu Takana
Heat — 46.26
Quarterfinals — 45.91
Semifinals — 45.88 (→ did not advance)
Men's 10,000 metres
Yutaka Kanai
Qualifying Heat — 28:14.67
Final — 28:27.06 (→ 7th place)
Masanari Shintaku
Qualifying Heat — 28:24.30
Final — 28:55.54 (→ 16th place)
Men's Marathon
Takeshi So
Final — 2:10:55 (→ 4th place)
Toshihiko Seko
Final — 2:14:13 (→ 14th place)
Shigeru So
Final — 2:14:38 (→ 17th place)
Men's Long Jump
Junichi Usui
Qualification — 8.02m
Final — 7.87m (→ 7th place)
Men's High Jump
Takao Sakamoto
Qualification — 2.21m (→ did not advance)
Men's Javelin Throw
Masami Yoshida
Qualification — 81.42m
Final — 81.98m (→ 5th place)
Kazuhiro Mizoguchi
Qualification — 74.82m (→ did not advance, 20th place)
Men's Hammer Throw
Shigenobu Murofushi
Qualification — 70.92m (→ did not advance)
Men's Pole Vault
Tomomi Takahashi
Qualifying Round — 5.30m
Final — no mark (→ no ranking)
Women's Marathon
Nanae Sasaki
Final — 2:37:04 (→ 19th place)
Akemi Masuda
Final — did not finish (→ no ranking)
Women's High Jump
Hisayo Fukumitsu
Qualification — 1.87m (→ did not advance, 17th place)
Megumi Sato
Qualification — 1.84m (→ did not advance, 18th place)
Women's Javelin Throw
Emi Matsui
Qualification — 57.72m (→ did not advance)
Minori Mori
Qualification — 56.60m (→ did not advance)
Boxing
Men's Light Flyweight (– 48 kg) Mamoru Kuroiwa First Round — Bye Second Round — Defeated Francisco Tejedor (COL), 4:1 Quarterfinals — Lost to Keith Mwila (KEN), 0:5
Men's Bantamweight (– 54 kg) Hiroaki Takami First Round — Bye Second Round — Defeated Gamaleldin El-Koumy (EGY), 4:1 Third Round — Lost to Dale Walters (CAN), 0:5
Canoeing
Cycling
Nine cyclists, eight men and one woman, represented Japan in 1984. Tsutomu Sakamoto won a bronze medal in the sprint event.
Men's individual road race
Matsuyoshi Takahashi — 45th place
Sprint
Tsutomu Sakamoto
Katsuo Nakatake
1000m time trial
Tsutomu Sakamoto
Team pursuit
Akio Kuwazawa
Harumitsu Okada
Mitsugi Sarudate
Yoshihiro Tsumuraya
Points race
Akio Kuwazawa
Hitoshi Sato
Women's individual road race
Wakako Abe — 40th place
Diving
Men's 3m Springboard
Isao Yamagishi
Preliminary Round — 427.14 (→ did not advance, 25th place)
Equestrianism
Fencing
Nine fencers, five men and four women, represented Japan in 1984.
Men's foil
Kenichi Umezawa
Nobuyuki Azuma
Tadashi Shimokawa
Men's team foil
Nobuyuki Azuma, Yoshihiko Kanatsu, Hidehachi Koyasu, Tadashi Shimokawa, Kenichi Umezawa
Women's foil
Azusa Oikawa
Mieko Miyahara
Miyuki Maekawa
Women's team foil
Mieko Miyahara, Azusa Oikawa, Miyuki Maekawa, Tomoko Oka
Gymnastics
Handball
Men's Team Competition
Preliminary Round (Group A) Lost to Yugoslavia (15:32) Lost to Romania (22:28) Lost to Iceland (17:21) Lost to Switzerland (13:20) Defeated Algeria (17:16) Classification Match 9th/10th place: Lost to United States (16:24) → 10th place