Background The diverse safety risk factors and their complex correlations in metro construction projects are important reasons for frequent safety accidents. However, existing studies have not yet explained fully the relationship among safety risk factors from the perspective of the sequence of factors. Objective The main objective of this study is to explore the temporal combination path of safety risk factors of metro construction projects. Methods The data are 80 metro safety accidents collected manually from the websites of government departments where the accidents occurred covering 18 provinces in China from 2007 to 2023. Grounded theory analysis was used to extract safety risk factors from accident reports, and temporal qualitative comparative analysis (TQCA) was used to explore the temporal combination path of safety risk factors. Results There are two kinds of temporal combination paths of safety risk factors for severe safety accidents, i.e., “environmental risk - equipment risk- management risk” and “management risk - environmental risk - equipment risk - worker operational risk”. While there are five kinds of temporal combination paths of safety risk factors for general safety accidents, namely “management risk - equipment risk”, “management risk - worker operational risk”, “worker operational risk - management risk”, “equipment risk - management risk - worker operational risk”, “environmental risk - management risk - worker operational risk”. Conclusions There is a typical temporal combination path of safety risk factors in metro construction safety accidents. These findings suggest that safety accidents can be effectively prevented by cutting off the path of safety risk factors.