OBJECTIVE: To explore the association between community engagement and life satisfaction amongst older adults, with a focus on the mediating effect of social capital and the moderating effects of gender and age. METHODS: This study used structural equation modelling to analyse data from a sample of 1036 older adults in Chengdu, China, examining both the direct and indirect effects of community engagement on life satisfaction through social capital, and whether the relations moderated by gender and age. Model fit was evaluated using χ, Comparative Fit Index, Root Mean Square Error of Approximation and Standardised Root Mean Square Residual to ensure the validity of the proposed relationships. RESULTS: The findings indicated a significant positive relationship between community engagement and social capital (β = .54) as well as between social capital and life satisfaction (β = .28). Social capital fully mediated the association between community engagement and life satisfaction. Moderation analysis revealed that the effects of community engagement and social capital on life satisfaction were stronger amongst older males (β = .57 and .32) than older females (β = .52 and .26). CONCLUSIONS: This study highlights the significant role of community engagement in enhancing social capital and life satisfaction amongst older adults in China, particularly for males and individuals aged 70 years or older. Findings indicate that policymakers should prioritise the development and implementation of community engagement programs specifically designed to support older men and individuals aged 70 years or older. It underscores the importance of culturally specific strategies for promoting active ageing in China.