Discriminant validity test.

The Chinese government’s environmental conservation efforts require the active participation of all society. This study investigated how internal and external efficacy influence pro-environmental behavior with environmental willingness as a mediator. This study employed a structural equation model to analyze the data from 1499 survey questionnaires. The analysis revealed that both internal and external efficacy can enhance individuals’ pro-environmental behavior in the private and public spheres. External efficacy has a stronger impact on environmental willingness and public sphere environmental behavior, while internal efficacy more significantly influences private sphere environmental behavior. Additionally, environmental willingness only mediates efficacy and public sphere environmental behavior. The innovation of this study is the examination of internal and external efficacy from the perspective of different sources and the comparison of their differential impacts on pro-environmental behavior. Relevant policies should effectively enhance residents’ internal and external efficacy to comprehensively improve their level of pro-environmental behavior.