Oikawa (written: 及川) is a Japanese surname. Notable people with the surname include:
Ataru Oikawa (及川 中, born 1957), Japanese film director
Azusa Oikawa (及川 あずさ, born 1960), Japanese fencer
Fumihiro Oikawa (及川 史弘, born 1973), Japanese figure skater and journalist
Koshirō Oikawa (及川 古志郎, 1883–1958), Imperial Japanese Navy admiral
Nao Oikawa (及川 奈央, born 1981), Japanese actress, television personality and AV idol
Okuro Oikawa (及川 奥郎, 1896–1970), Japanese astronomer
Seijin Oikawa (及川 誠人, born 1970), Japanese motorcycle racer
Oikawa Teruhisa (及川 煌久, born 1936), Japanese sumo wrestler
Yūya Oikawa (及川 佑, born 1981), Japanese speed skater
Fictional characters:
Hazuki Oikawa (及川 葉月), a character in the manga series Moyasimon: Tales of Agriculture
Tooru Oikawa (及川 徹), a character in the manga series Haikyuu!!
Yukio Oikawa (及川 悠紀夫), a character in the anime series Digimon Adventure
Fish
Zacco platypus (オイカワ、追河)
