Iwasa is a Japanese surname. Notable people with the surname include:Iwasa Matabei , Japanese artist Janet Iwasa, American cell biologist and animator Mayuko Iwasa , Japanese gravure idol Misaki Iwasa , Japanese idol and singer Ryosuke Iwasa , Japanese boxer SakutarÅ Iwasa , Japanese anarchist Shun Iwasa , Japanese general Taku Iwasa , Japanese professional wrestler Yoh Iwasa, Japanese academic