The purpose of this study is comparing attentional bias in patients with obsessive - compulsive disorder (OCD) with matched healthy individuals. In this cross - sectional study 46 patients with obsessive-compulsive disorder are compared with 46 healthy individual by means of convenient sampling. Emotional Stroop test is used for evaluation. Data were analyzed through Student t-test. Finding shows significance difference between two groups (P value < 0.05). Correct response is more in healthy groups that patient (p = .04). Attention bias in OCD patient might be caused difficulties in disengagement and inhibition of attention to threaten stimuli.