This chapter focuses on pancreatic acinar cell carcinoma and related tumors, presenting 5 cases: acinar cell carcinoma (2 cases, including one misdiagnosed as neuroendocrine tumor and one with intraductal growth), mixed acinar-ductal adenocarcinoma, and adult pancreatoblastoma. Each case details patient demographics, clinical manifestations, laboratory results, imaging findings (via CT/MRI), pathological examinations (gross, microscopic, immunohistochemistry), and definitive diagnoses. Discussions emphasize differential diagnosis from similar pancreatic lesions (e.g., neuroendocrine tumors, ductal adenocarcinoma), key pathological and imaging features of each tumor type, and the value of multi-modality imaging combined with histopathology in accurate diagnosis, providing clinical references for managing these rare pancreatic neoplasms.