In order to accurately evaluate the wall quality of cement-soil mixing wall by TRD method and reduce the risk of foundation pit excavation, this paper proposes a comprehensive evaluation method of wall quality. Based on strength analysis, impermeability analysis, borehole TV analysis and electromagnetic borehole radar analysis, the main influencing factors of TRD cement soil wall quality are analyzed and determined. Using the analytic hierarchy process, the hierarchical structure model of the wall quality evaluation index system is established and the evaluation factors are quantified. The fuzzy comprehensive evaluation method is used to evaluate the index factors. By analyzing the evaluation results, the evaluation grade standards of excellent, good, medium and poor reflecting the wall quality are established. The evaluation system and grade standard are used to evaluate the wall quality of waterproof curtain in a station foundation pit of Qingdao metro. The actual excavation of the foundation pit is basically consistent with the evaluation results. It has preliminarily realized a change from qualitative and empirical to scientific and half quantitative. The research results can be promoted and applied to the similar TRD cement soil mixing wall project in the future.