Objective The aim of this study is to investigate whether insight and mentalizing abilities are related to the severity of Obsessive Compulsive Disorder (OCD) in treatment resistant OCD. We look at the association between treatment resistance, insight, and mentalizing ability. Methods The study was conducted with 71 OCD patients; 30 of them met the criteria for treatment resistant OCD, whereas the other 41 (57.7%) were labeled as responder group. All patients were assessed with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Reading the Mind in the Eyes Test (RMET), Brown Assessment of Beliefs Scale (BABS), Mini International Neuropsychiatric Interview, Beck Depression Inventory, and Beck Anxiety Inventory. Results The resistant group received higher depression and anxiety mean scores and had significantly longer illness duration. The RMET score was significantly higher for responders. The Y-BOCS insight score and the BABS score were significantly higher for the resistant group. BABS scores were negatively correlated with RMET total scores. RMET scores were found to be significant predictor of insight even when other potential factors were controlled for. Conclusion Results suggest that better mentalizing abilities may be a predictor of better treatment outcome in patients with OCD.