Facilities provided by social network sites allow individuals to use social networks for various purposes such as communication, entertainment and information sharing. These purposes vary depending on the social networks individuals use and on their personality traits. The present study examined preservice teachers' social network use purposes with respect to their personality traits. The participants of the study were 660 preservice teachers attending a Turkish university. For data collection in the study "Scale of Social Network Use Purposes" and "Basic Personality Traits Inventory" were used. The research data were analyzed using Pearson Correlation Analysis and Multi-Linear Regression Analysis. The findings revealed that among the personality traits, conscientiousness, openness to experience and negative valence were predictors of the sub-factors of social network use purposes. As for other personality factors, neuroticism and extraversion were not significant predictors of the total social network use purpose score or its sub-factors.