The presence of hepatic changes in ulcerative colitis ranges from 4.7% to 90% and the mechanisms are not clear. This study had the purpose to verify their frequency, observe the relation between clinical forms and hepatic lesions and identify the possible histological changes in the liver. We studied 21 patients with ulcerative colitis (Group 1, subdivided in Group 1A non-alcoholic and 1B alcoholic) and compared with 10 patients with irritable bowel syndrome (Group 2). The study involved clinical evaluation, ultrasonography liver function tests and needle biopsy of the liver, performed by laparoscopy, when necessary. Clinical alterations were present in three patients. The ultra-sonographic study was altered in 14.3% in Group 1A and in 57.1% in Group 1B. The albumin and cholinesterase levels were the most frequent abnormality in ulcerative colitis. In irritable bowel syndrome (Group 2), these exams were normal. Liver biopsy was performed in 15 patients and variable degrees of histologic changes were present in all.