Results for Japan in 400 metres, Men

Olympic and Intercalated results only.

Games	Athlete/Team	Placement
1912 Summer Olympics	Yahiko Mishima	2 h4 r1/3
1920 Summer Olympics	Gensabulo Noguchi	DNS
	Shinichi Yamaoka	DNS
1924 Summer Olympics	Tokushige Noto	5 h6 r2/4
1928 Summer Olympics	Iwao Aizawa	DNS
1932 Summer Olympics	Iwao Masuda	6 h1 r2/4
	Seikan Oki	6 h2 r2/4
	Zhang Hsing-Hsien	5 h5 r1/4
1936 Summer Olympics	Toyoji Aihara	4 h7 r1/4
	Keiji Imai	5 h5 r1/4
	Hiroyoshi Kubota	6 h4 r1/4
1952 Summer Olympics	Junkichi Matoba	3 h4 r1/4
	Eitaro Okano	DNS
1956 Summer Olympics	Kanji Akagi	AC h1 r1/4
1960 Summer Olympics	Hirotada Hayase	6 h1 r1/4
1964 Summer Olympics	Hirotada Hayase	6 h7 r1/4
1972 Summer Olympics	Yoshiharu Tomonaga	6 h4 r2/4
1984 Summer Olympics	Susumu Takano	8 h1 r3/4
1988 Summer Olympics	Susumu Takano	5 h1 r3/4
1992 Summer Olympics	Susumu Takano	8
	Takahiro Watanabe	5 h9 r1/4
1996 Summer Olympics	Shigekazu Omori	4 h3 r1/4
2000 Summer Olympics	Jun Osakada	8 h2 r2/4
	Takahiko Yamamura	5 h1 r1/4
	Kenji Tabata	6 h8 r1/4
2004 Summer Olympics	Jun Osakada	5 h1 r1/3
	Mitsuhiro Sato	5 h3 r1/3
	Yuki Yamaguchi	5 h7 r1/3
2008 Summer Olympics	Yuzo Kanemaru	7 h4 r1/3
2012 Summer Olympics	Yuzo Kanemaru	4 h5 r1/3
2016 Summer Olympics	Julian Walsh	6 h4 r1/3
	Yuzo Kanemaru	8 h7 r1/3
2020 Summer Olympics	Julian Walsh	6 h4 r1/3
2024 Summer Olympics	Fuga Sato	DNSh1 r2/4
	Yuki Joseph Nakajima	DNSh2 r2/4
	Kentaro Sato	DNSh3 r2/4