Preschool onset of obsessive-compulsive disorder (OCD) is rare with limited studies on it and with multiple diagnostic and treatment quandaries. We report a case of 5-year-old girl who had obsessive-compulsive symptoms since 4 years of age. She was diagnosed based on Diagnostic and Statistical Manual of Mental Disorders, 5th edition criteria after eliminating other potential diagnoses. She showed good response to a combination of parent-assisted exposure and response prevention therapy and fluoxetine. This case brings into focus the distress associated with very early onset of OCD and discussion of differential diagnoses and treatment options for it.