Abstract: In this paper, a new method based on TOPSIS is proposed, which is based on the comprehensive analysis method of TOPSIS. The importance degree, the importance degree of the structure and the key importance degree are used as the analysis index to construct the integrated and quantitative Analytical method. At the same time, according to the problem that the result of TOPSIS parameter is subjective and the result is weak, the entropy weight coefficient is used to quantitatively determine the parameter weight. In addition, the concept of detection priority is proposed to solve the problem of the same result, and the bottom events with the same analysis result are sorted and the exact diagnosis sequence is obtained. It is found that the diagnostic sequence generated by this method has some improvement effect compared with the traditional method in terms of accuracy and scientificity.