Objective To investigate the CT imaging features of autoimmune pancreatitis (AIP) with report of 4 cases and literature review. Methods The CT imaging data of 4 AIP patients proved on the basis of clinical findings, laboratory tests, response to steroids therapy and follow-up observation were retrospectively collected. Plain CT and contrast-enhanced dual phase CT scan at arterial and portal venous phases were performed for all 4 patients. All imaging data were reviewed, focusing on the shape, size, parenchyma density and enhancement patterns of the pancreas, as well as the biliary and pancreatic ducts, peripancreatic fat, blood vessels, retroperitoneal spaces, lymph nodes, and other positive findings. Results Three patients showed diffuse swelling of the pancreas on CT and 1 had focal enlargement of pancreatic head. Swelled pancreas was hypodense on plain CT images, showed decreased enhancement on artery phase and moderate enhancement on portal venous phase images of contrast-enhanced CT. Capsule-like enhanced rim was found around swelled pancreas in 2 patients. Stricture of distal common bile duct was present in 2 patients, and ERCP showed irregular narrowing of the main pancreatic duct in 1 cases. After steroid therapy, all patients showed significant morphological improvement of the pancreas at follow-up CT examination. Conclusion CT scan reveals certain characteristic imaging findings of AIP, thus it is helpful for the diagnosis of AIP.