The benefits of using social network sites (SNS) have spurred heated debate in academia and popular culture alike. This study sought to address the debate by formulating a new, nuanced framework highlighting two conceptual distinctions: (a) preference for versus problem in one's interpersonal relations, and (b) SNS use versus the benefits of such use. Mixed-effects meta-analysis was performed in 178 independent samples from seven regions worldwide (n = 108,068; age range = 13-68). Eligible studies were those that examined an association between at least one common proxy measure of the socially rich (vs. poor; i.e., extraversion, social anxiety, or loneliness) and a criterion measure (i.e., SNS use or online social capital). The results revealed a complex picture. SNS use was positively correlated with both extraversion and social anxiety, although the social anxiety-SNS use correlation was significant for adult samples rather than adolescent samples. Online social capital was positively correlated with extraversion but inversely correlated with loneliness. Our conclusion is that extraverted individuals use SNS to enhance their opportunities for social interactions and can acquire more online social resources, whereas adults who are socially anxious use SNS to compensate for their social deficits but such effort is unrelated to online social resource accumulation. Individuals who feel lonely tend to obtain few such resources. However, most of the studies examined the leisure use of Facebook. We advocate more thorough testing of our hypotheses in future research on therapeutic SNS use and/or the use of SNS other than Facebook. (PsycINFO Database Record (c) 2019 APA, all rights reserved).