Though social media is considered to enhance environmentally conscious behaviour, there has not been sufficient investigation on the effects of specific affordances pertaining to green social networks (GSN). Also, the mechanism by which these affordances affect pro‐environmental behaviour (PEB) has not been explored in depth. Addressing these research gaps, this study first introduces three context‐specific GSN affordances, such as green self‐identification, green broadcasting, and green social endorsement. Further, drawing inspiration from social influence theory and the Stimulus‐Organism‐Response framework, the study put forth a novel framework that explains the varying effects of the conceptualized GSN affordances on PEB through the mediating mechanism of collective intention. The framework also indicates perceived informational and emotional values as moderators that accentuate the indirect influence of GSN affordances on PEB. Adopting a time‐lagged multi‐wave online survey design, 314 valid responses were obtained. The results of the moderated mediation analysis reveal that: (1) collective intention partially mediates the relationships between green broadcasting and PEB, and between green social endorsement and PEB; (2) collective intention fully mediates the relationship between green self‐identification and PEB. Further, the indirect effect of green self‐identification on PEB is positively moderated by emotional values and not moderated by informational values. Interestingly, the indirect effects of green broadcasting and green social endorsement on PEB are positively moderated by both informational and emotional values. These findings offer significant implications for researchers and practitioners who look out for online communities to promote actual PEB.