Introduction: The purpose of this research was to investigate the role of behavioral activation/inhibition systems and social anxiety in the prediction of students' Internet addiction. Methods: This study used a descriptive-correlative design. For this purpose, 356 students were selected through random cluster sampling from Arak University (172 males and 184 females). They were asked to answer the Behavioral Inhibition/Activation Systems Scale, Internet Addiction Test and Social phobia Inventory. Then, the correlation and regression analyses were employed. Results: The results indicated that social anxiety is significantly and positively correlated with Internet addiction, there was no significant relationship between Internet addiction and behavioral activation systems, and behavioral inhibition systems were significantly and positively correlated with Internet addiction. Regression analysis showed that social anxiety and behavioral inhibition systems could predict Internet addiction. Conclusion: Based on the present study results, it can be concluded that social anxiety and behavioral inhibition system predicted higher levels of Internet addiction.
