Sei Hiraizumi (平泉 成, Hiraizumi Sei, born on June 2, 1944 in the former Nukata, Aichi) is a Japanese actor. In 1964, Hiraizumi joined Daiei Film company and started his acting career. In the 1970s to early 1980s, he appeared a lot of jidaigeki and detective television dramas as a guest villain actor.