Objective: The research was to examine the associations among passive use of social network site, self-con- cept clarity, and depression. Methods: Scales for passive use of social network site, self-concept clarity, and depression were administered to 1205 undergraduate students. Results: ①Passive use of social network site was positively correlated with depression, while self-concept clarity was negatively correlated with both passive use of social network site and depres- sion. ②Self-concept clarity fully mediated the relation between passi...