Sima Lang (171–217), courtesy name Boda, was a government official who lived during the late Eastern Han dynasty of China.
He was the eldest among the eight sons of Sima Fang, who served as the Intendant of the Capital (京兆尹) during the reign of Emperor Ling, He was described as a big and tall man (approximately 1.91 metres).
In his early years, he took the tests required to serve as an official in the Han government and briefly held the position of a civil service cadet.
In 189, when the warlord Dong Zhuo seized control of the Han central government, Sima Lang managed to escape with his family and return to his hometown.
When he held office, Sima Lang adopted policies which benefited the common people, and thus earned their respect in return.