This study aims to investigate the validity and reliability of the Turkish version of Internet Gaming Disorder Questionnaire.The Experimental Sample of this study included 1161 students aged between 10 and 18 from four different schools. Language equivalence study of the questionnaire was conducted by two experts one of whose native language was English and fluent in Turkish, and the other, vice versa. Reliability of the questionnaire was evaluated by Test-retest method and Cronbach's alpha internal consistency analysis. Construct validity of the questionnaire was examined by confirmatory factor analysis. SPSS and -MPLUS 6.1- softwares were used for statistical analyses.Cronbach's alpha coefficient for internal consistency was 0.86. Total score correlations varied between 0.23 and 0.70 (p<0.01). Test-retest score averages did not differ for both the total and subgroup scores. Test-retest correlation was calculated as 0.865 (p<0.01). Confirmatory factor analyses for construct validity showed that factor loadings of items varied between 0.165 and 0.785. Cut-off score of the questionnaire was determined as 69 after Cluster analyses and ROC analyses.This study concluded that the validity and reliability of the Turkish version of Internet Gaming Disorder Questionnaire developed by Pontes et al. were satisfactory.