Empress Gemmei (or Gemmyo 元明天皇) (661–722) was the 43rd imperial ruler of Japan and the fourth woman to hold such a position. She was a daughter of Emperor Tenji of Japan and the wife of Kusakabe no miko, who was the son of Emperor Temmu of Japan and Empress Jito of Japan. Kusakabe was also Gemmei's first cousin and her nephew. After their son, Emperor Mommu died in 707, she succeeded to the throne, in hopes of holding it until her grandson, Shomu, reached maturity. However, in 715, Gemmei abdicated in favor of Mommu's sister Gensho. Shomu later succeeded Gensho.

In 708 she moved the capital city of Japan from Fujiwara to Heijo-Kyo, west of the modern city of Nara, thus giving the Nara period of Japanese history its name.