Emperor Kangxi (4 May 1654 ??0 December 1722) was the fourth ruler of the Qing Dynasty and the second Qing emperor to rule over China proper, from 1661 to 1722.

Kangxi's reign of 61 years makes him the longest-reigning Chinese emperor in history (although his grandson, the Qianlong Emperor, had the longest period of de facto power) and one of the longest-reigning rulers in the world. However, having ascended to the throne at the age of seven, he was not the effective ruler until later, with that role temporarily fulfilled for six years by four regents and his grandmother, the Grand Empress Dowager Xiaozhuang.