Introduction: The most common finding related to nonalcoholic steatohepatitis is obesity, but severe malnutrition status can also be induced by steatohepatitis. The authors describe here hepatic pathological findings in a rare case of steatohepatitis leading to hepatic decompensation caused by malnutrition after pancreaticoduodenectomy. Case: A 68-year-old female patient, who had been previously diagnosed with pancreatic cancer, and had undergone pancreaticoduodenectomy five months before this presentation, visited with abdominal distension. Routine computed tomography three months after surgery revealed severe fatty liver but no evidence of tumor recurrence. Since pancreaticoduodenectomy, her food intake had reduced and as a result, she had lost 7 Kg of body weight over 2 months. At this admission, computed tomography revealed moderate amounts of ascites without tumor recurrence. Furthermore, her albumin and lipid profile levels were markedly decreased, and she had a flapping tremor and slurred speech suggestive of hepatic encephalopathy. Liver biopsy findings were consistent with steatohepatitis and showed macrovesicular steatosis without definite fibrosis. After careful nutritional control, her symptoms disappeared and her laboratory findings improved. Conclusion: This case suggests poor nutritional status after pancreaticoduodenectomy in pancreatic cancer patients can induce severe liver steatosis and hepatic decompensation, and that there is a need to monitor and support nutritional status in these patients.