Empress Kōken (孝謙天皇) or Shōtoku (称徳天皇) (718-770) was the 46th imperial ruler of Japan. She first ruled as Kōken from 749 to 758. She abdicated in favor of her second cousin, Junnin, but six years later she took the crown from him and reascended the throne. Her posthumus name for her second reign (764-770) was Shōtoku.

Today, she is remembered chiefly for conducting an affair with a Buddhist monk named Dokyo, a man on whom she heaped titles and power. The affair illustrated the growing power of the Buddhist priesthood and was a prime factor in Emperor Kammu's decision to move the capital away from Nara in 784.

Shotoku died of smallpox, after which she was succeeded by her first cousin twice removed, Emperor Konin. She should not be confused with Prince Shotoku (572-622), who was one of the first in Japan to sponsor Buddhism.

Preceded by: Shomu	Empress of Japan	Succeeded by: Junnin
Preceded by: Junnin	Empress of Japan	Succeeded by: Konin

de:Koken it:Koken imperatrice del Giappone nl:Keizerin Koken ja:孝謙天皇 zh-cn:孝谦天皇