As the proliferation of social media and live streaming, online celebrity endorsement is a common practice of content marketing in e-commerce platform. Despite the prevalent use of social media and online community, empirical research investigating the economic values of user-generated-content (UGC) and marketer-generated-content (MGC) still lags. This study seeks to contribute theoretically and practically to an understanding of how online celebrity endorsement and fans interaction behaviors affect e-commerce sales. We adopt cross-sectional regression to assess the economic value of online celebrity endorsement, and we employ panel vector autoregressive model to explain the dynamic relationship between marketers’ and consumers’ content marketing behaviors and e-commerce product sales. Empirical results highlight that the interaction within fans community has spillover effect on content marketing under “Fan Economy” era.