Abstract : The present study was to evaluate the relationship between ADHD and DAT1, DRD4, and DRD5 genes in adolescent. This was a case-control study that included 24 adolescents the aged of 12-19 years old. DNA isolation was made to determine methylation status of DAT1, DRD4 and DRD5 genes. The obtained data was analyzed using SPSS 21 program and descriptive analysis, Pearson correlation, Spearman correlation, Fisher t-test, Kolmogorov-Smirnov, and Mann-Whitney U test were used. Methylation levels of DAT1, DRD4 and DRD5 genes in adolescent with ADHD adolescents with ADHD were compared with case and control group. There was no statistically significant difference between the two groups. However, moderately significant correlations were found between the scale scores given to the participants in the case group and the control group the methylation levels of the DAT1, DRD4 and DRD5 genes. As a result, DAT1, DRD4 and DRD5 genes found to be correlated with total methylation or methylation levels of CpG islets. The role of DNA methylation in ADHD etiopathogenesis has been shown. The results will be important for genetic, neuroimaging and neurochemical evaluations.