Background & Aims : Nowadays, in considering the significant role of the Internet in different fields especially in research, Internet anxiety is an important issue. This study determines the relationship between the personality variables with the Internet anxiety of the students of both Mazandaran University of Medical Sciences and Sari Islamic Azad University.

  Materials & Methods : This was a descriptive-analytical study. The population included all students studying in Mazandaran University of Medical Sciences and Sari Islamic Azad University in 2011. 342 university students participated in this study selected by stratified randomly method. For gathering data a questionnaire including demographic data and NEO questionnaire was used. For analyzing the data, descriptive and inferential statistics including one sample t-test, Pearson Correlation Coefficient, Multi Variable Regression, and t-test questionnaire were used.

  Results : The findings showed that the students had lower level of anxiety than the average (P<0/0. 000). Neurosis also had reversed relation with anxiety and extraversion (r=-0. 26, P<0. 05). Openness, Agreeable, and being conscientious had direct relation with the Internet anxiety. Among these five great personality factors inventory, only neurosis and being conscientious could predict the Internet anxiety.

  Conclusion : As neurosis and being conscientious of the five NEO personality characteristics have power to predict Internet anxiety, these two features can be used for preventing the development of Internet anxiety.