Abstract: To assess the severity of acute pancreatitis (AP) using computed tomography (CT) severity index (CTSI) and modified CT severity index (MCTSI), to correlate with clinical outcome measures, and to assess concordance with severity grading, as per the revised Atlanta classification (RAC). Material and Methods: This is a prospective and descriptive study conducted in the Department of Radiology at a Maheshwara Medical College. A total of 50 patients enrolled with the chief complaint of epigastric pain, nausea and vomiting and CECT abdomen were suggestive of acute pancreatitis were included in this study. Assessment of severity of acute pancreatitis was done in all cases by Balthazar CTSI scoring and Mortele Modified CTSI scoring. Results: In our study total 50 cases of acute pancreatitis cases were included in the study. Out of 50 cases, 36 (72 %) were male and 13 (26%) were females. We found that acute pancreatitis was found three times more common in males than in females. Cholelithiasis was found to be most common aetiological factor for acute pancreatitis in 48% cases followed by alcoholic pancreatitis was seen in 26% of cases. Least Aetiological factor such as Trauma and drug induced. Pleural effusion was the most common extra-pancreatic complication, 27 patients (54%). Left pleural effusion was more common than the right, and in none of the cases, isolated right sided pleural effusion was found. Ascites was the second most common complication seen in 9 patients (18%). Conclusion: In conclusion CECT was found to be an excellent imaging modality for diagnosis, establishing the extent of disease process and in grading its severity. The Modified CT Severity Index is a simpler scoring tool and more accurate than the Balthazar CT Severity Index. In this study, it had a stronger statistical correlation with the clinical outcome, be it the length of hospital stay, development of infection and occurrence of organ failure. It could also .....................