Susumu Hagiwara (Japanese: 萩原 生長; November 6, 1922 – April 1, 1989) was a Japanese-born American physician and neuroscientist. Hagiwara was born and raised in Hokkaido, Japan, attending the University of Tokyo for his M.D. and Ph.D. degrees. He became a professor at the Tokyo Medical and Dental University before migrating to the United States to serve as professor for both the University of California, San Diego and University of California, Los Angeles. Hagiwara died of a heart attack at his Los Angeles home on April 1, 1989.