Abstract: Wang Ang’s handwritten annotation Songyuan Tongjian is the sole existing edition, which is collected in Hubei Library now. It has about 600 Wang’s annotations, totaling 12000 words, and is a precious resource for studying Wang Ang’s thoughts. These annotations point out the problems of historical events and erroneous writing in Songyuan Tongjian, which provides multiple references for organizing and researching Songyuan Tongjian. There are two completely different evaluations about Songyuan Tongjian in the Ming and Qing dynasties. Wang’s handwritten annotation is also an important material for showing the change of two evaluations mentioned above.