Understanding virtual community (hereinafter as VC) participation is of importance to VC organizers as well as VC researchers. Although VC participation has been explored from diverse perspectives, few studies can offer a comprehensive theoretical framework to explain why people participate in VCs. This article contributes to VC research by proposing and empirically validating an exploratory theoretical framework from the interpersonal relationship perspective using two interpersonal relationship theories—the Triandis interpersonal behavior model from social psychological angle and fundamental interpersonal relationship orientation from communicational angle to explain two types of VC participation—behavior to obtain information and behavior to give information. Data were collected in three representative VCs. Data analysis results showed that the two interpersonal relationship theories are effective in explaining VC participation. This article contributes to the existing body of knowledge on VCs by providing an integrative interpersonal relationship framework to explain VC participation, that is, members participate in VCs to satisfy their interpersonal relationship needs at three levels—inclusion, control, and affect through the dynamic interpersonal process expressed as covert to overt psychological process.