Sima Yi (pronunciation ⓘ 司馬懿; 179 CE – 7 September [1] 251 CE), courtesy name Zhongda, was a Chinese military general, politician, and regent of the state of Cao Wei during the Three Kingdoms period of China.

Sima Yi (onyomi: Shiba I) is an intellectual who is accredited as the ancestral founder of Western Jin. Once he agreed to serve the Cao family, he became one of Cao Pi 's close friends and subsequently an influential figure in Wei, cunningly defending himself from his many detractors.

Sima Yi (179–251) was a general, politician and regent of the state of Cao Wei (220–266) in the Three Kingdoms period (220–280) in China. Two of his sons, Sima Shi (208–255) and Sima Zhao (211–265), rose to power in the 250s and consecutively served as regents throughout the reigns of the last three Wei emperors.

Sima Yi can refer to: Sima Yi (father of Sima Zhao), the ancestor of the imperial family of Sima Jin; Sima Yi (Prince of Changsha), the prince of Western Jin who participated in the War of the Eight Princes; Sima Yi (Prince of Piling), the son of Sima Wei, Prince of Chu; Sima Yi (emperor), the emperor of Eastern Jin

Sima Yi (司馬懿), styled Zhongda (仲達), born in Wen County, Henei Prefecture (Presently Wen County in He Nan Province). “A skilled advisor of the Wei kingdom. His efforts laid the foundation of Jin.”

The Advisors Alliance is a 2017 Chinese two-part television series based on the life of Sima Yi, a government official and military general who lived in the late Eastern Han dynasty and Three Kingdoms period of China.

Sima Yi is a playable and historical character featured in Total War: Three Kingdoms. He is one of the Strategist class heroes in his faction. Blessed with great intelligence from a young age, Sima Yi is one of China 's greatest strategists.