Background & Objectives: Major depression and obsessive - compulsive disorders have some comorbidities. The objective of this study is to compare perfectionism and its components in patients with depression, obsessive - compulsive disorders and normal individuals. Materials & Methods: The current study was conducted in cross-sectional context.   The study population included all patients who referred to the clinics, psychiatric centers and counseling centers in the city of Tabriz. The sample was divided into three groups, one group of 30 with a diagnosis of obsessive - compulsive disorders, another group of 30 with a diagnosis of major depression disorder, and the other 30 were normal. Participants answered to Hill perfectionism questionnaire. To analyze the data, multivariate analysis of variance was used. Results: The results showed that the mean scores of perfectionism and its positive- negative dimensions were higher in patients with obsessive - compulsive and depression disorders, in comparison with normal individuals. Also no significant differences in perfectionism and its positive- negative dimensions scores was observed between people with these two mentioned disorders. Conclusion: The perfectionism components are common component in obsessive - compulsive and major depression disorders.