To reveal the psychological adaptation mechanisms of college freshmen in the digital age, this study explored the relationship between body image self-discrepancy and social media use motivations, as well as the role of social anxiety between them. A survey was conducted among 1,350 first-year college students using the Body Image Assessment Scale, the Social Anxiety Scale, and the Social Media Use Motivation Scale. The results indicated that there is a significant positive correlation between body image self-discrepancy and social anxiety, as well as a significant positive correlation between social anxiety and the social media use motivation. Meanwhile, social anxiety plays a significant mediating role between body image self-discrepancy and motivations for social media use. Moreover, the mediating effect of social anxiety is more pronounced in the female group compared to the male group. Integrating Self-Discrepancy Theory and the Online Social Compensation Theory, this research provided theoretical and practical references for universities to build online support systems that promote freshmen’s interpersonal adaptation.

body image self-discrepancy, social anxiety, social media use motivation, online social compensation, college freshmen