Although previous research indicates that participation in a brand community may foster consumer loyalty to the brand in question, research has seldom examined the mediating effect of community commitment on brand commitment. Drawing from the typologies of organizational commitment, we divide community commitment into three components: continuance community commitment (continuance CC), affective community commitment (affective CC), and normative community commitment (normative CC). We then assess the mediating role of brand attachment in the relationship between these three components and brand commitment. We test the hypotheses using a sample of online mobile phone brand communities in China. The empirical results reveal that brand attachment exerts an indirect (but not mediated) effect on the relationship between continuance CC and brand commitment and on the relationship between normative CC and brand commitment. We also find that it exerts a partial mediating effect on the relationship between affective CC and brand commitment. The findings contribute to the branding literature and have important implications for brand community management.