Objective: Tourette disorder composed of history of multiple motor tics and at least a vocal tic during a period of such disorder. Many reports have investigated in co– morbid major depressive disorder, and studies signify such importance of early diagnosis and treatment. So diagnosis of major depressive disorder when it is comorbid with Tourette disorder considered to be important in our society as well.

Materials & methods: 30cases of Tourette disorder who refferred to a child psychiatry center were studied during a period of one year in a descriptive. Cross sectional study. At the same time” 30 cases matched by age and sex were chosen as our control group from Tehran public schools. There were 25 boys and 5 girls in each group “with age rang of 8 to 18 years. A semistructural questionnaire of kiddy Schedule for Affective Disorder and Schizophrenia was used to investigate the presence of major depressive disorder in both groups. Statistical tests including MC- Nemar exact test were used for statistical analysis.

Results: 23/3% of Tourette group patients were diagnosed as major depressive while 3.3% of the control group was diagnosed as major depressive disorder” .

Conclusion: As given the high association rate for Tourette disorder and major depressive disorder. It is suggested to investigate all cases of Tourette disorder for possible major depressive disorder.