Background: Compulsive behaviours describe obsessive compulsive disorder (OCD) and autism spectrum disorder (ASD). According to available data, up to 20% of those seeking treatment for OCD also have autistic characteristics. The impact of autistic characteristics on OCD is unknown. Objective: To find the frequency of autistic traits in patients with OCD and its effect on clinical characteristics of OCD. Subjects and Methods: A case control cross-sectional study design was employed. The Autism-Spectrum Quotient (AQ) was used to assess autistic features in 60 adult outpatients with DSM-5 OCD diagnoses and 60 adults who were age and sex matched from the general population. On demographic and clinical criteria, OCD patients with and without autistic symptoms were compared. Results about 30% of patients scored above the clinical threshold of the Autistic-Spectrum Quotient (AQ). Patients with autistic features had a considerably higher level of OCD symptom severity as judged by the Yale-Brown Obsessive-Compulsive Scale (p = 0.04) and a significantly higher level of insight impairment as measured by the Brown Assessment of Beliefs Scale (p = 0.001). Conclusion: OCD patients have a high frequency of autistic characteristics. Autistic features are linked to more severe OCD symptoms and a lack of insight. Key words: autistic spectrum disorder, autistic traits, co-morbid, Obsessive Compulsive Disorder