Emperor Yuan of Jin (; 276 – 3 January 323), personal name Sima Rui (司馬睿), courtesy name Jingwen (景文), was an emperor of the Jin Dynasty and the first of the Eastern Jin. His reign saw the steady gradual loss of Jin territory in the north, but entrenchment of Jin authority south of the Huai River and east of the Three Gorges, and for generations Jin was not seriously threatened by Wu Hu kingdoms to the north.