Ōkawa, Okawa, Ookawa or Ohkawa (written: 大川 or 大河, literally "big river") is a Japanese surname. Notable people with the surname include:

, Japanese fencer Hisayuki Okawa (born 1971), athlete Misao Okawa (1898–2015), Japanese supercentenarian Nanase Ohkawa (born 1967), Japanese manga writer Ryuho Okawa (1956–2023), religious and political leader Shūmei Ōkawa (1886–1957), Japanese nationalist, Pan-Asian writer, indicted war criminal, and Islamic scholar , Japanese plasma physicist Tōru Ōkawa (born 1960), Japanese actor , Japanese AV idol