Sima Zhen

{{Short description|Historian from China}}

{{distinguish|Sima Qian}}

{{family name hatnote|Sima (Ssu-ma)|lang=Chinese}}

{{Chinese

|t=司馬貞

|s=司马贞

|p=Sīmǎ Zhēn

|w=Ssu¹-ma³ Chen¹

}}

Sima Zhen ({{zh|t=司馬貞|w=Ssu-ma Chen}}; 679–732), courtesy name Zizheng (Tzu-cheng; 子正), was a Tang dynasty Chinese historian born in what is now Jiaozuo, Henan.

Sima Zhen was one of the most important commentators on the Shiji.{{cite book | title=The Cloudy Mirror: Tension and Conflict in the Writings of Sima Qian| url=https://books.google.com/books?id=v-v6UhTMJRIC| last=Durrant| first=Stephen W.| date=January 1995 | publisher=SUNY Press| page=xx| isbn=9780791426555 }} His commentary is known as the Shiji Suoyin ({{lang|zh-hant|史記索隱}}), which means "Seeking the Obscure in the Records of the Grand Historian".{{cite book | title=Sima Zhen Shiji Suoyin Shuolie| last=Zhu| first=Dongrun| year=1940| pages=141–163| publisher=Kaiming Shudian| location=Chengdu}}