Empress Kōken (718 – August 28, 770), also known as Empress Shōtoku, is the 46th and the 48th monarch of Japan respectively, according to the traditional order of succession.

Empress Kōken first reigns from 749 to 758, then she reascends the throne as Empress Shōtoku from 765 until her death in 770.

In the history of Japan, Kōken/Shōtoku is the sixth of eight women to take on the role of empress regnant.

The five female monarchs before Kōken/Shōtoku ware (a) Suiko, (b) Kōgyoku/Saimei, (c) Jitō, (d) Gemmei, and (e) Genshō; and the two women sovereigns reigning after Kōken/Shōtoku are (f) Meishō, and (g) Go-Sakuramachi.