Masashi Matsuie (Japanese: 松家仁之, Hepburn: Matsuie Masashi; born 1958) is a Japanese novelist and editor. He worked for the publishing house Shinchosha, where he helped launch the translated-fiction imprint Shincho Crest Books and served as founding editor-in-chief of the quarterly magazine Kangaeru hito. His 2012 debut novel Kazan no fumoto de won the 64th Yomiuri Prize for Literature. His 2017 novel Hikari no inu won the Kawai Hayao Story Prize and the Art Encouragement Prize of the Minister of Education, Culture, Sports, Science and Technology.