The aim of this study was to determine the difference in the effectiveness of exposure-response prevention therapy and emotion-focused therapy on uncertainty intolerance and cognitive emotion regulation in patients with obsessive-compulsive disorder. The present study method was a semi-experimental pre-test-post-test with a two-month follow-up with a control group. The statistical population in this study was all people with obsessive-compulsive disorder in Babol city in the fall and winter of 1402. 45 people were selected by simple random sampling method and then randomly assigned to three groups of 15 people (n=45). Then, the therapeutic intervention was implemented on the experimental groups and a post-test was held after the end of the intervention period. In order to follow up on the durability of the effects of the treatments, a two-month follow-up was conducted. The first experimental group received a summary of the exposure-response prevention therapy package during 10 90-minute sessions and the second group received a summary of the emotion-focused therapy package during 8 90-minute sessions, and the control group did not receive any intervention. In order to analyze the data, a mixed analysis of variance test was performed using SPSS version 26. The results showed that the effectiveness of exposure-response prevention therapy and emotion-focused therapy on intolerance of uncertainty and adaptive cognitive emotion regulation in patients with obsessive-compulsive disorder is statistically significant. In addition, the effectiveness of exposure-response prevention therapy in reducing intolerance of uncertainty in patients with obsessive-compulsive disorder is greater than that of emotion-focused therapy.