Today, organizations require additional efforts to develop new streams of revenue as competition is intense and new customers are hard to secure at a mature stage. The advent of social networking sites serves as an alternative tactic for organizations to form online brand communities, engage customers and hence foster brand loyalty. This article presents a research model of antecedents and consequences of customer engagement in online brand communities on social networking sites. Specifically, we examined how system support, community value, freedom of expression, and rewards and recognition encourage customer engagement, as well as how customer engagement influences repurchase intention and word-of-mouth intention. We tested the research model with a sample of 276 online brand community members. Empirical data supported our hypotheses, and revealed that customer engagement mediates relationships between community characteristics and brand loyalty. The current study validated the propositions from prior conceptual frame- works, and shed light for practitioners and scholars.