Nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) usually occurs in patients with metabolic syndrome. However, it can develop in relation with pancreaticoduodenectomy (PD) independent of insulin resistance. NAFLD/NASH potentially progresses to liver cirrhosis and subsequent end-stage liver disease, but in general the disease progression is very slow. We here report the case of a 57-year-old Japanese woman who underwent PD for pancreatic head cancer, subsequent to which she developed rapidly progressive NASH without prior liver diseases, resulting in death due to hepatic failure 5months after PD. Marked body weight loss was a distinguishing clinical feature. Severe malnutrition induced by pancreatic exocrine insufficiency, postoperative eating disorder and exacerbation of diabetes mellitus were thought to be etiologically associated with the rapid progression of her disease. This case suggests the necessity of close hepatic surveillance as well as nutritional evaluation followed by prophylactic pancreatic enzyme replacement and nutritional supply after PD.