The psychometric properties of the Turkish version of the Internet Gaming Disorder Scale Objective: The main aim of the current study was to test the psychometric properties of the Internet Gaming Disorder Scale (IGDS), both the long (27-item) and short (9-item) polytomous versions, which are survey instruments that measure Internet gaming disorder (IGD) on the basis of the 9 criteria from the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).Method: Participants were evaluated by applying the 27-item IGDS and the Young’s Internet Addiction TestShort Form (YIAT-SF). The psychometric properties of the IGDS were tested through an online survey completed by volunteers who are university students in Ankara, active Internet game players, as well as individuals who are in the e-mail database of an Istanbul-based company which organizes e-sports tournaments. Results: A single component on the nine-item IGDS reached the criterion of an Eigenvalue greater than one (5.926), and the variance accounted for by this component was 65.85%. Confirmatory factor analyses demonstrated that the structural validity (i.e., the dimensional structure) of the nine-item IGDS was satisfactory. This short version of the scale was also reliable (i.e., internally consistent with Cronbach’s α of 0.931) demonstrating good criterion-related validity, as indicated by positive correlations with time spent playing games, and the YIATSF score. Correlation between the 27-item IGDS and the nine-item IGDS was very high (n=457; r=0.988, p<0.001). Test-retest correlation for both the 27-item IGDS (n=261, r=0.759) and nine-item IGDS (n=261, r=0.756) were high. When the DSM-5 threshold for diagnosis (experiencing 5 or more criteria) was applied, the prevalence of disordered gamers ranged between 3.9% and 9.2%, according to the cutoff point chosen for each item. Conclusion: The results of the validity and reliability testing of the Turkish version of the nine-item IGDS were found to be similar to the findings of the original scale. These findings support the Turkish versions of the nineitem IGDS, which measure a unidimensional construct as being valid and reliable IGD screening instrument in determining IGD which can become problematic among young adults and also for the purposes of early diagnosis and use in other relevant research