BACKGROUND It is important to avoid relapse in autoimmune hepatitis (AIH) because repeated multiple relapses have been associated with a worse prognosis. However, risk factors for relapse before initiation of treatment are not fully understood. The aim of this study was to find predictive markers for relapse of type 1 AIH. MATERIAL AND METHODS We reviewed the records of 53 patients diagnosed with type 1 AIH based on the revised scoring system proposed by the International Autoimmune Hepatitis Group (IAIHG) between 2009 and 2014 at 4 hospitals belonging to the Saga Study Group of Liver Diseases (SASLD). We analyzed the differences in background characteristics between patients with or without relapse. RESULTS All patients achieved remission after treatment, and 9 (17%) subsequently relapsed. The relapsed patients were significantly younger and had a higher positive rate of anti-smooth muscle antibody (ASMA) than the non-relapsed patients (100% vs. 25%, P=0.0012). Moreover, relapse rate increased with titer of ASMA, while titer of antinuclear antibody was not associated with relapse rate. CONCLUSIONS ASMA is a useful predictive marker for relapse of type 1 AIH during or after withdrawal of medical therapy. More careful attention should be paid to immunosuppressive therapy in patients with high titers of ASMA.