Dai Zhen (Chinese: 戴震; pinyin: Dài Zhèn; Wade–Giles: Tai Chen, January 19, 1724 – July 1, 1777), courtesy name Shenxiu(慎修), art name Dongyuan(東原), was a Chinese philosopher of the Qing dynasty.

Hailing from Xiuning, Anhui Dai was a versatile scholar who made great contributions to mathematics, geography, phonology and philosophy.

In 1733, Dai was recruited by scholar Ji Yun to be one of the editors of the official encyclopedia and collection of books, Siku Quanshu.

In particular, two criticisms that Dai made were: First, Neo-Confucianism focused too much on introspective self-examination whereas truth was to be found in investigation of the external world.

Second, he criticized the Neo-Confucian drive to eliminate human desire as an obstacle to rational investigation.