The use of social networking sites has become normal part of our daily lives and more and more researchers are interested how it impacts us. Still, research examining use of social network from the Selfdetermination theory perspective is lacking. So in this research, by using the framework of the Selfdetermination theory, we try to examine the relationship between some characteristics of use of social networks, students’ basic psychological needs satisfaction, and life satisfaction. It has been hypothesized that basic psychological needs satisfaction mediate relationship between some characteristics of use of social networks and life satisfaction. The sample consisted of 294 female students of Early childhood and preschool education from University of Zagreb and Zadar. Students were asked why they use social networks, amount of time they spend daily on social networks and how many contacts they have on social networks. In addition to that, participants filled two questionnaires: The Satisfaction with Life Scale and Basic Psychological Need Satisfaction Scale. The results show that students who have more social contacts have less satisfied basic psychological needs. On the other hand, life satisfaction is not significantly related to the number of contacts on social networks. It has been shown that students who spend more time on a daily basis on social networks are less satisfied with basic psychological needs. The results also showed that there are differences in satisfying the content of life satisfaction with regard to the reason why respondents use social networks. Respondents who are most often used by social networks for entertainment are more satisfied with life than those who use networks because of boredom or because they have others, but alike to those who use them for some other reason. Therefore, we can conclude that basic psychological needs are mediated in the relationship between the characteristics of using social networks and life satisfaction