Background: Ulcerative colitis is an inflammatory chronic disease which is believed to be a multi organ condition. The prevalence of ulcerative colitis is reportedly increasing in Iran presenting with the same clinical characteristics as in developing countries. Pulmonary manifestations of ulcerative colitis are increasingly reported. In this study, we investigated the incidence of bronchial hyper-responsiveness (BHR) in ulcerative colitis (UC) patients.Materials and Methods: Fifty-one UC patients with definite diagnosis referred to Shariati Hospital, Tehran, Iran, were selected to be evaluated with methacholine challenge test from October 2010 to October 2011. Patients were compared for their methacholine test outcome and its association with age, sex, diagnosis time, and disease activity.Results: The median age was 41 (range 15 to 65) years. The median time of diagnosis was 7 (range<1 to 16) years. Forty-five percent were females, 18% had active disease and 13% had comorbidity. Nine percent of patients with UC had abnormal PFT in our study. Three cases (5%) had bronchial hyper-responsiveness that was not correlated with sex, age, time of diagnosis, or disease activity.Conclusion: A small number of ulcerative colitis patients in our study had disturbed pulmonary function test which is in concord with the findings of other studies. However, higher rates of bronchial hyper-responsiveness have been reported in other studies. Confounding factors like cigarette smoking and medications, which were negative or minimal in our study, may influence the results.