Background: Today, computer games have taken a prominent place in the lives of children and teenagers, and statistics indicate that online gaming constitutes the majority of computer usage. Numerous studies have explored the detrimental effects of internet gaming on individuals. However, to date, no comprehensive research has been conducted specifically investigating the effect of online gaming on academic performance within a medical education context. To address this gap, we have conducted this study, focusing on the impact of online gaming on the academic performance of Iranian medical students. Methods: In a cross-sectional study, 185 medical students from four disciplines ((basic sciences, Physiopathology, extern, intern) were selected through a multi-stage sampling method at Mashhad University of Medical Sciences. Internet gaming disorder (IGD) test as well as the grade point average (GPA) of the last academic semester, the average study hours on normal days and near the exam, the efficiency of study hours, the number of failed semesters, and academic satisfaction were assessed. Results: In this study, a total of 185 medical students participated, of which 62.2% (115 students) were females. The prevalence of IGD was found to be 3.8%. Interestingly, the prevalence of IGD was approximately four times higher in males than in females (7.1% vs. 1.7%, P=0.106). Furthermore, both the overall daily study time (P<0.001) and the daily study time on days near exams (P=0.031) were found to be significantly higher in students without IGD compared to those with IGD. However, factors such as age, gender, being native to Mashhad, discipline level, last GPA, number of failed semesters, and satisfaction with education showed no correlation with IGD. Conclusion: These findings may serve as a cautionary signal for educational authorities within the Iranian medical education system. However, to obtain more robust results, further investigations are recommended, particularly in other academic majors.