The accident rate is high in subway maintenance work, and most of the accidents are caused by human factors, especially the lack of sensitivity to risk perception, the lack of rigorous attitude towards safety and the lack of safe citizenship behavior (SCB). Therefore, it is very important to study the risk perception (RP), safety attitude (SA) and SCB of metro maintenance staff in order to reduce the accident rate. In order to reduce human errors and accidents, this study analyzed the influence of metro maintenance staff’s RP on their SCB and the mediating role of SA. Based on previous studies, this paper uses the risk perception scale, safety attitude scale and safety citizenship behavior scale as research tools. A survey was administered at the Subway Company, and altogether 268 valid questionnaires were used, and the data were analyzed by SPSS19.0 (IBM, Armonk, NY, USA) and AMOS 24.0 (IBM, Armonk, New York, NY, USA). The result reveals that SA plays a complete mediating role between metro maintenance staff’s RP and their SCB; and SA has a positive influence on SCB; RP has a positive influence on SA; and SA positively predicts SCB.