Autoimmune pancreatitis (AIP) is a rare inflammatory disease. AIP has characteristic histology, serology and imaging findings. Two types of AIP exist, type 1, which is a part of the systemic immunoglobulin G4-related disease, and type 2, which is only localized to the pancreas. Patients with type 1 are predominantly older men, have involvement of other organs and more often experience relapse than patients with type 2. Both types respond well to steroid treatment. The most important differential diagnose is pancreatic cancer.