Research has revealed that passive social network site (SNS) use might undermine subjective well-being. However, less is known about the mediating and moderating mechanisms underlying this relationship. The current study tested the mediation effect of envy in the association between passive SNS use and low subjective wellbeing, and whether this mediating process was moderated by gender. A sample of 707 Chinese university students (mean age = 19.06 years, SD = 1.12) completed anonymous questionnaires regarding passive SNS use, envy, and subjective well-being, Results revealed that the association between passive SNS use and low subjective well-being was mediated by envy. Moreover, the mediating effect of envy was moderated by gender, with the effect being stronger for females. These findings contribute to our understanding of how and for whom passive SNS use predict low subjective well-being, and suggest the need to take gender into account in prevention and intervention programs for problematic SNS use. (C) 2017 Published by Elsevier Ltd.