BackgroundResearch is scarce with regard to the role of psychotic and schizotypal symptoms in treatment of obsessive-compulsive disorder (OCD). The aim of the current study was to investigate the occurrence and specificity of psychotic and schizotypal symptoms among non-psychotic OCD patients, and to examine whether such symptoms was associated with response to exposure and response prevention (ERP), and whether ERP for OCD had an impact on psychotic and schizotypal symptoms.MethodsNon-psychotic OCD patients (n = 133) and a general non-psychotic psychiatric outpatient sample (n = 110) were assessed using self-report inventories before and after psychological treatment.ResultsNon-psychotic OCD patients did not report greater degree of psychotic or schizotypal symptoms than the control group. Psychotic and schizotypal symptoms were not associated with OCD symptoms before or after ERP. Psychotic and schizotypal symptom were significantly reduced following ERP.ConclusionsPsychotic and schizotypal symptoms seem to be equally prevalent among non-psychotic OCD patients and non-psychotic psychiatric controls. These symptoms were more linked to depressive symptoms than OCD symptoms. In non-psychotic OCD patients, ERP seems sufficient in reducing OCD symptoms despite the presence of psychotic- and schizotypal symptoms, and reductions in psychotic- and schizotypal symptoms were observed following ERP.