There are several different opinions on the location of the imperial garden "West Garden" in the research on the building history of the Middle Capital of Jin Dynasty. This disagreement also involves issues on the location of other imperial gardens such as Tongle Garden and Qionghua Island. Based on the building history context during Northern Song to Yuan period of the Middle Capital and the Souther Capital of Jin Dynasty, this paper reexamines historical poetry and prose materials related to "West Garden" which adopted by different opinions to demonstrate the location of the West Garden in the Middle Capital of Jin Dynasty. Combined with the life of the poet and the intensive reading and analysis of the content of the poem, it is pointed out that there was an imperial garden in the same name "West Garden", also called "Tongle Garden", in the Southern Capital of Jin Dynasty, which was formerly the Longde Palace and Xiefang Garden constructed by the Huizong in Northern Song Dynasty. Because the West Garden (Tongle Garden)'s name in the Southern Capital was duplicated with the imperial gardens in the Middle Capital, historical text materials about the West Garden in Southern Capital were wrongly used by some research in the past to demonstrate the location of West Garden of the Middle Capital. Thus, the author first discriminates the historical text materials about the West Garden in the Middle Capital from that in the Southern Capital. Then, three pieces of historical circumstantial evidence are added to clarify that the West Garden of the Middle Capital, an imperial garden with Taiye Pool and Qionghua Island as the main body, should be located in the west of Wanning Palace in the northeast suburb, about the area of Beihai and Zhonghai today.