太宰治（日语：太宰 治，1909年6月19日－1948年6月13日），本名津岛修治（津岛 修治／つしま しゅうじ），生于日本青森县、无赖派小说家。

太宰治从学生时代起已希望成为作家，21岁时和银座咖啡馆女侍投海自杀未遂。1936年出版之《晚年》一书中作品《逆行》列为第一届芥川赏的候选作品。结婚后，写出了《富岳百景》及《斜阳》等作品，成为当代流行作家。1948年6月13日深夜与崇拜他的女读者山崎富荣跳玉川上水自杀，得年39岁，留下了《人间失格》等作品。

Osamu Dazai(太宰 治,Dazai Osamu, June 19, 1909 – June 13, 1948) was a Japanese author who is considered one of the foremost fiction writers of 20th-century Japan. A number of his most popular works, such as The Setting Sun (Shayō) and No Longer Human (Ningen Shikkaku), are considered modern-day classics in Japan. With a semi-autobiographical style and transparency into his personal life, Dazai’s stories have intrigued the minds of many readers. His books also bring about awareness to a number of important topics such as human nature, mental illness, social relationships, and postwar Japan.