Emperor Suizei (綏靖天皇) was the second imperial ruler of Japan to appear on the traditional list of emperors.

No firm date can be assigned to this emperor and he is regarded by historians as a "legendary emperor". He was the first one of eight emperors without legend. In Kojiki and Nihonshoki only his name and genealogy were recorded. His historical existence was traditionally believed and a tomb was attributed to him, but contemporary studies support the view no such person existed.

According to the sources he was a son of Jimmu. Soon after he succeeded his father, his brother rebelled against him. His posthumous name literally means "joyfully healthy peace."