Sumi Shimamoto (島本 須美, Shimamoto Sumi?), real name Sumi Koshikawa (越川 須美, Koshikawa Sumi?), is a veteran Japanese voice actress born on December 8, 1954, in Kochi, Kochi Prefecture, Japan. After graduating from the Toho Gakuen College of Drama and Music, she joined Gekidan Seinenza, a theatrical acting troupe. She is currently independent of any talent management company.
She is married to Daisuke Koshikawa, one of the founders of the comedy troupe Chibikko Gang.