Autoimmune hepatitis is a chronic liver inflammation resulting from deregulation of immune tolerance mechanisms. Multiple sclerosis is also an inflammatory disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged. Here we present a case of an 18 year old female with multiple sclerosis who was treated with glatiramer acetate and with interferon beta 1a. Seven months after initiating treatment, liver dysfunction occurred. Clinical and laboratory findings were suggestive of drug-induced hepatitis, which led to the discontinuation of treatment with interferon, with clinical improvement. However facing a new episode of acute hepatitis one year later, this time without interferon, she was subjected to a liver biopsy, and the analysis of autoantibodies was positive for smooth muscle antibodies. Given the diagnosis of autoimmune hepatitis she started therapy with prednisolone and azathioprine, with good clinical and analytical response. Moreover, the demyelinating lesions of multiple sclerosis ameliorated. This is one of the few cases that describe the association of autoimmune hepatitis with multiple sclerosis, and there is a chance both diseases have the same autoimmune inflammatory origin