In order to study the clinical effect of bilateral capsulotomy in patients with refractory obsessive compulsive disorder (OCD), 35 patients with refractory obsessive compulsive disorder for whom anti-OCD medications and psychological/behavior therapy had failed, underwent MRI-guided stereotactic bilateral anterior capsulotomy. Pre- and post-operative Yale-Brown obsessive compulsive scale (Y-BOCS), Hamilton depression scale (HAMD) and Hamilton anxiety scale (HAMA) scores were determined by psychiatrists. All patients underwent fluorodeoxyglucose positron emission tomography evaluation before and 6 months after the operation. Twenty patients became OCD symptom-free (57%), 10 experienced significant improvement (29%) and five experienced no significant improvement (14%). There were significant decreases in Y-BOCS, HAMD and HAMA scores. Our results show that MRI-guided stereotactic bilateral capsulotomy is a precise, safe and effective therapy for refractory obsessive compulsive disorder. This promising technique may also improve anxiety and depression in addition to OCD. OCD patients who have not responded to medication, psychotherapy or behavioral therapy might benefit from MRI-guided stereotactic bilateral capsulotomy.