Non-alcoholic fatty liver disease (NAFLD) commonly is associated with chronic inflammatory bowel disease (CIBD) and usually is considered to be stable and benign. However, NAFLD -- and in particular its subset, non-alcoholic steatohepatitis (NASH) -- may lead to progressive liver disease. Moreover, NAFLD sensitizes the liver to injury and increases the risk of developing acute-on-chronic liver failure following a "third hit". We here present one patient with NASH, as probably induced by long-standing Crohn's disease in the absence of ethanol consumption or abuse. The patient acquired an acute HBV infection and died from complications. As based on the clinical and histological findings, Crohn's disease appears to be a risk factor for developing NAFLD and thus to contribute to the progression into NASH. In conclusion, we suggest that Crohn's disease-related NAFLD may increase the vulnerability of the liver, which indicates that patients with a known history of CIBD merit special attention.