Objective: Although acute pancreatitis (AP) is a self-limited disease under supportive and medical treatment, it can have life-threatening potential in some patients. Results of studies reporting outcomes of AP-associated pancreatic malignancy are controversial. The aim of this study was to evaluate the severity and prognosis of pancreatic cancer (PC)-related AP by modified Balthazar score. Methods: A total of 354 patients hospitalized and followed up in our clinic between 2013 and 2019 were included in the study. Demographic data of all patients were recorded. The etiology of all cases was determined. According to the etiology, the cases were divided into 2 groups: AP related to pancreatic malignancy and AP due to nonmalignant causes. The patients underwent computed tomography of the abdomen within the first 12 hours of admission and after 3 to 7 days. Patients were evaluated and classified by modified Balthazar classification. Results: Malignancy-related AP was detected in 18 (5.1%) patients. A total of 336 cases (94.9%) were related to nonmalignant causes. There was no statistically significant difference in the severity of AP in both groups at admission and after 3 days (p> 0.05). The changes (regression, progression, or no change) in the disease severity at the first and the subsequent imaging were examined. There was no significant relationship between the 2 groups (p> 0.05). Conclusion: AP may be the clinical manifestation of PC or PC may induce AP in various ways. It was shown that the underlying malignancy did not adversely affect the severity and course of AP.