Nowadays, the Internet and social networks are used extensively and sometimes pathologically. Thus, this study aimed to investigate the role of borderline personality traits and rejection sensitive in predicting membership in social networks. In this descriptive and correlational study, among 200 high school teachers (111 females and 89 male) of Khusfe city, South Khorasan province, 182 teachers were selected by census method and then they were asked to complete borderline personality scale, rejection sensitive questionnaire and a questionnaire on membership in social networks. To test the hypotheses, Pearson correlation coefficient and multivariate regression analysis were used. Results showed that rejection sensitivity and borderline personality traits had a role in predicting membership in social networks and these two variables accounted for 27% variance of membership in social networks. It seems that having borderline personality traits and rejection sensitivity in actual interpersonal relations are effective factors in a tendency to use social networks more and compulsorily.
