Over the past decade, electronic word-of-mouth communication (EWOM) has become more salient in online contexts. However, the extant literature on EWOM has largely depended upon theories developed in traditional offline contexts. We proposed that both individual and social settings should not be ignored in the study of EWOM and sought to integrate two perspectives: social influence and social identity. More specifically, we examined the impact of cognitive and emotional social identities on social influence. While both types of social identities were positively associated with social influence, the strength of influence varied depending on the type of products being consumed. We also found that fewer members identified with communities where there were high discrepancies in members’ product expertise. Conversely, more members identified with communities where they had strong ties. These findings had strong theoretical and practical implications on EWOM.