This paper introduces a novel theoretical lens of pseudo-community trust and studies its effect on member disclosure on social networking sites (SNSs). We collect survey data from 229 SNS users and validate the research model using the structural equation modeling method. Findings indicate the effect of pseudo-community trust in promoting member self-disclosure and reveal the contingency of its effect. Moreover, our findings report important antecedents to pseudo-community trust and evidence their indirect effects on member self-disclosure through pseudo-community as a mediator. This research contributes to the trust literature and self-disclosure literature on SNSs.