Emperor Xiaowu of Jin (362–396), personal name Sima Yao, courtesy name Changming, is an emperor of the Eastern Jin Dynasty (265–420) in China.

During his reign, Jin sees his dynasty survive a major attempt by Former Qin to destroy it, but he will nevertheless be the last Jin emperor to actually exercise imperial power, as his sons Emperor An and Emperor Gong will be controlled by regents and warlords.

He himself dies an unusual death—he is killed by his concubine Consort Zhang after he insults her.