Steroid therapy appeared to be a standard treatment for autoimmune pancreatitis (AIP), although some AIP patients improve spontaneously. The indications for steroid therapy in AIP patients are symptoms such as obstructive jaundice, abdominal pain, and back pain, and the presence of symptomatic extrapancreatic lesions. Before steroid therapy, jaundice should be managed by biliary drainage in patients with obstructive jaundice, and blood glucose levels should be controlled in patients with diabetes mellitus. For the initial oral prednisolone dose for induction of remission, 0.6 mg/kg/day is recommended. The initial dose is administered for 2-4 weeks, and the dose is tapered by 5 mg every 1-2 weeks, based on changes in the clinical manifestations, biochemical blood tests (such as liver enzymes and IgG or IgG4 levels), and repeated imaging findings (US, CT, MRCP, ERCP, etc.). The dose is tapered to a maintenance dose (2.5-5 mg/day) over a period of 2-3 months. Steroid therapy should be stopped based on the disease activity in each case. Stopping of maintenance therapy should be planned within at least 3 years in cases with radiological and serological improvement. Re-administration or dose-up of steroid is effective for treating AIP relapses. The prognosis of AIP appears to be good over the short-term with steroid therapy. It is unclear whether the long-term outcome is good because there are many unknown factors, such as relapse, pancreatic exocrine or endocrine dysfunction, and associated malignancy.