Wang Zhen (died August 1449, Hebei province, China) was a Chinese eunuch who monopolized power during the first reign of the Ming emperor Yingzong (reigned as Zhengtong; 1435–49).
Wang was denounced by later historians as the first of a series of eunuchs whose mismanagement helped destroy the Ming dynasty (1368–1644). Wang was the constant companion and personal servant of the emperor Yingzong (1427–64), who ascended the throne while still a boy. Isolated from his peers, the young emperor was dominated by Wang even after he came of age.
Ignoring the counsel of the regular military leaders, Wang persuaded the emperor to embark on a war against the Oirat branch of the Mongol tribes, who had rapidly increased their power along China’s northwestern borders under the leadership of Esen Taiji. The imperial army was ambushed about 50 miles (80 km) northwest of Beijing, the emperor was captured, and Wang and all the leading Chinese generals were slain.