Although standard treatment for autoimmune hepatitis (AIH) comprises prednisolone (PSL) and azathioprine (AZA), some patients are intolerant to or do not respond to PSL and/or AZA. The clinical practice guidelines of AIH in Europe and North America recommend mycophenolate mofetil (MMF) as second-line treatment in these patients. We administered MMF as second-line therapy to 7 patients with AIH (male/female 1/6, age range 27-79 years) who were intolerant to or failed to respond to standard treatment. At the commencement of MMF, the median ALT value was 84U/L (28-254U/L), and the PSL dose was 15.0mg/day (0-45mg/day). In terms of adverse effects of PSL, diabetes mellitus was observed in 4 patients (insulin injection in 2) and femoral head necrolysis in 2. Adverse effects of AZA were present in 2, and 5 patients were not treated with AZA. At 24 weeks of MMF treatment, the median ALT and daily PSL dose were decreased to 16U/L (6-41U/L) and 7.0mg, respectively. Blood sugar control improved, and insulin injection was discontinued in both the patients. While intractable diarrhea developed in 1 patient with cirrhosis, no adverse effect was observed in other 6 patients. In conclusion, MMF appeared effective and safe in at least non-cirrhotic patients with AIH who were intolerant or failed to respond to standard treatment with PSL and AZA in Japanese clinical practice.