This mixed-method study explored the influences of professional learning communities (PLCs) on teachers' job satisfaction in China. A questionnaire survey was administered to 488 teachers in 16 primary schools in Shanghai to examine the effect of PLCs on teachers' job satisfaction. Follow-up qualitative interviews with 10 teachers were conducted to explain the reasons behind such effects. The results show that the organisation-centric characteristics of PLCs, comprising supportive leadership, organisational structure and cultural barriers, have significant and positive effects on the teacher-centric characteristics of PLCs (i.e., collaborative inquiry and sharing and shared purpose and responsibility), which further significantly and positively predicted teacher job satisfaction. The practical implications of the findings and suggestions for future research are discussed.