Abstract: To fully guarantee the safety and order of subway construction as well as understand the status of safety accidents during subway construction, a subway construction safety accident risk evaluation system was constructed in the paper. 230 nationwide safety accidents of subway construction were evaluated by the principal component analysis. The results indicate that there is a high risk in collapse accidents and object strikes that should be avoided by many measures. Even though there is not high risk in vehicle injury, its consequences is serious, which shall be paid more attention. The conclusion demonstrate that the risk of subway construction safety accidents can be objectively evaluated by the principal component analysis, which could provide a guidance for subway construction managers to prevent and control the occurrence of safety accidents.