Abstract: Existing data-driven transient stability assessment makes extensive use of features of generation-load modes, but fails to fully reflect the influence of the fault location on the system transient stability. In this paper, a continuous fault location representation method with electrical meaning is proposed based on the electrical distance. The fault location representation method is applied to the transient stability assessment, which accomplishes the unified feature expression of fault locations. First, based on the electrical distance, the concept of the electrical coordinate system is proposed to represent fault location quantitatively. Then,the optimization method for reference points of the electrical coordinate system is studied, and the fault location features are extracted accurately. Finally, the proposed representation method of fault locations is applied to the transient stability assessment,and the fault location is considered uniformly based on the electrical coordinate system in the transient stability assessment. The validity of the proposed method is verified with a provincial power grid in China as the example.