The development of de novo autoimmune liver disease after liver transplantation (LT) has been described in both children and adults. Reported herein is a case that is best characterized as post-LT de novo hepatitis with features of autoimmune hepatitis (AIH)-primary biliary cirrhosis (PBC) overlap. A 56-year-old man underwent LT for decompensated liver disease secondary to non-alcoholic steatohepatitis. His liver function tests became markedly abnormal 8 months after LT. Sequential liver transplant biopsy findings were confusing and shared findings seen with both AIH and PBC. Although standard autoimmune serological tests were negative, a dramatic biochemical response was observed to a regimen consisting of prednisone, mycophenolate mofetil, and ursodeoxycholic acid added to maintainance tacrolimus. The donor was histocompatibility leukocyte antigen, DR4, positive, a haplotype associated with the development of AIH-PBC overlap syndrome. In conclusion the authors believe that this may be a case of post-LT de novo overlap syndrome of AIH-PBC, a novel 'autoimmune-type' response.