Previous research offers equivocal results regarding the effect of social networking site use on individuals’ self-esteem. We conduct a systematic literature review to examine the existing literature and develop a theoretical framework in order to classify the results. The framework proposes that self-esteem is affected by three distinct processes that incorporate self-evaluative information: social comparison processes, social feedback processing, and self-reflective processes. Due to particularities of the social networking site environment, the accessibility and quality of selfevaluative information is altered, which leads to online-specific effects on users’ self-esteem. Results of the reviewed studies suggest that when a social networking site is used to compare oneself with others, it mostly results in decreases in users’ selfesteem. On the other hand, receiving positive social feedback from others or using these platforms to reflect on one’s own self is mainly associated with benefits for users’ self-esteem. Nevertheless, inter-individual differences and the specific activities performed by users on these platforms should be considered when predicting individual effects.