The aim of this research is to study the dependency of students on social networks based on demographic variables. This applied and quantitative research carried out in survey design. The measurement tool for the study was a social networks addiction subscale adopted from questionnaire of Arslan & Kırık (2013).  The reliability of tool based on Cronbach's alpha was 0.932. The content validity of tool was measured by view of specialist and construct validity was measured by factor analysis. The population of the study was 4771 undergraduate students at Azarbaijan Shahid Madani University and the sample size was 368 cases based on stratified random sampling method. SPSS software was used in descriptive and inferential statistics. Based on Pearson correlation test, the relationship between students’ dependency on social networks and Internet/social network rate of usage at 99 percent confidence level was positive and significant. Based on independent t-test, there was a significant difference in students’ social network dependency based on accommodation type. Based on ANOVA test, there was significant difference at 95 percent confidence level based on domain of study. Students’ dependency on social networks was in midpoint level. The students, who had further daily Internet or social network usage, had more dependency on networks. Students’ dependency on social networks with different levels of academic achievement was moderately similar. Dependency on social networks among two groups of students (dormitory/humanities domain) was more.