Results for Japan in 400 metres Individual Medley, Men

Olympic and Intercalated results only.

Games	Athlete/Team	Placement
1972 Summer Olympics	Jiro Sasaki	23
1976 Summer Olympics	Tsuyoshi Yanagidate	16
1984 Summer Olympics	Shinji Ito	13
1988 Summer Olympics	Yoshiyuki Mizumoto	17
	Takahiro Fujimoto	25
1992 Summer Olympics	Takahiro Fujimoto	8
	Toshiaki Kurasawa	DQ
1996 Summer Olympics	Toshiaki Kurasawa	10
	Tatsuya Kinugasa	11
2000 Summer Olympics	Shinya Taniguchi	8
	Susumu Tabuchi	13
2004 Summer Olympics	Jiro Miki	7
	Susumu Tabuchi	18
2012 Summer Olympics	Kosuke Hagino	3	Bronze
	Yuya Horihata	6
2016 Summer Olympics	Kosuke Hagino	1	Gold
	Daiya Seto	3	Bronze
2020 Summer Olympics	Daiya Seto	9
	Yuki Ikari	11
2024 Summer Olympics	Tomoyuki Matsushita	2	Silver
	Daiya Seto	7