This study adopts the brand relationship perspective to investigate the effects of social media-based brand communities on social marketing performances. An empirical study was conducted to examine the proposed hypotheses. Two analyses, one with 152 survey respondents on Weibo and the other with 209 survey respondents on Facebook, revealed that most of the antecedents (with the exception of monetary needs fulfillment) including information needs fulfillment, entertainment needs fulfillment, and social interaction needs fulfillment had positive effects on brand relationship quality for both Weibo and Facebook. Further, we found that brand relationship quality had positive effects on fans’ behavioral intentions toward brands, including willingness to buy, member continuance intention, and electronic word of mouth intention. This study contributes to research that shows brand relationship quality can be improved via a social media-based marketing approach. Implications corresponding to the research findings as well as study limitations and future directions are also discussed.