In recent years research studies have tackle the issue of brand fan economy and their behaviours, however little is known about brand evangelism. Given that many consumers are crazy in love with brand fan page on Facebook, understanding how fans behave in brand fan page is crucial in determining brand evangelism. Our main goal is to understand how different dimensions of social capitals in online fan page exert influence on brand love and how the underlying mechanism in turn facilitates consumers to develop brand evangelism. By using partial least square (PLS), the results show that the three dimensions of social capital impose differing effects in influencing the establishment of brand love and its consequent effect on brand evangelistic behaviours in SNS. It is found that relational capital in brand fan page serves as the most influential antecedent to drive brand love. The findings of this study have significant implications to both marketers and researchers.