Improving the job satisfaction of vocational education teachers (VET) is necessary for maintaining the stability of the vocational education teaching force and is an essential support for enhancing the professional attractiveness and ensuring the quality of VET. Unlike previous studies, firstly, in terms of groups, the particular group of teachers in this study focuses on VET, which in reality is often overlooked compared to other groups of teachers due to the low level of recognition of vocational education (VE) in China. Secondly, this phenomenon is more prominent and less researched regionally in economically underdeveloped areas due to the uneven and disparate economic development between the East and West of China. In terms of sample size, previous studies have lacked large samples, making it difficult to obtain convincing and realistic results. Finally, most previous studies considered teachers’ job satisfaction (TJS) in terms of external or internal factors alone. However, this study considers a combination of the external factor of the school climate (SC) in which VET works and the internal factor of teachers’ self-efficacy (TSE) to explore the relationship with TJS and its impact. Based on data from a survey of 1035 teachers in China, a structural equation model estimation method was used to explore and analyze the impact of SC and TSE on their TJS and the specific role of the relationship. The research found that VET-perceived SC is positively predicting TJS; VET-perceived SC is positively predicting TSE; TSE is positively predicting TJS; TSE significantly mediates the relationship between SC and TJS. This study provides a theoretical perspective that integrates the external organizational influences of SC and introduces the internal psychological factor of TSE as a mediating variable to understand TJS. In practice, it helps raise the importance of VET and provides empirical data and intellectual support to the relevant government departments in improving TJS.