PURPOSE: To assess the prognostic value of computed tomography (CT) in acute pancreatitis, initial CT examinations were classified into 5 grades in terms of the degree of disease severity and CT findings were correlated with clinical course, objective prognostic signs, and complications. MATERIALS AND METHODS: In 29 consecutive patients with acute pancreatitis, the CT examination and clinical course were reviewed without knowledge of each other finding. Both Ranson's prognostic signs and modified Glascow prognostic signs were used for evaluation of acute pancreatitis. RESULTS: Of the 29 patients, 25 patients recovered with medical treatment while 4 patients (14%) developed pseudocysts and the other 4 patients (14%) developed abscesses. CT findings of the acute pancreatitis are as follows; 10 patients (35%) in grade A with normal pancreas, 2 patients (7%) in grade B with pancreatic enlargement, 2 patients (7%) in grade C with intrinsic pancreatic abnormalities associated with haziness, 3 patients (10%) in grade D with single, ill-defined fluid collection, and 12 patients (41%) in grade E with extensive and two or multiple fluid collections or presence of gas in or adjacent to the pancreas. Correlation coefficient is 0.46 (p=0.012) between CT findings and Ranson's prognostic signs, 462 (p=0.0115) between CT findings and modified Glascow prognostic signs. CONCLUSION: CT gradings of acute pancreatitis may be useful in predicting clinical course.