This study employs a uses and gratifications approach to explore how social network sites (SNS) users' attachment style influences SNS motives, SNS use, and related psychological outcomes, as well as the interrelationships of these factors. By modifying preexisting attachment styles, users were classified into four styles: (1) fearful-avoidant, (2) dismissive-avoidant, (3) secure, and (4) anxious-ambivalent. Findings show SNS use and SNS-related outcomes differ across attachment style groups, although SNS motive does not; and attachment style moderates the influences of SNS motive and SNS use on psychological outcomes. These findings imply potential consequences of SNS use can substantially differ depending on users' attachment style.