Nishioka (written: lit. "western hill") is a Japanese surname. Notable people with the surname include:
, Japanese footballer , Japanese businessman and politician Hayward Nishioka (born 1942), American judoka , Japanese footballer , Japanese women's basketball player Rodger Nishioka, American educator , Japanese fencer , Japanese politician , Japanese boxer , Japanese carpenter , Japanese martial artist , Japanese academic , Japanese baseball player , Japanese swimmer , Japanese tennis player Ryusei Nishioka (西岡隆成, born 2003), Japanese trampoline gymnast