Acute stomach disease in elderly patients often lacks characteristic clinical manifestations. Presentations may differ from those in younger patients and are often complicated by concomitant diseases, delayed presentation, and misdiagnosis. Incorrect diagnosis and treatment can lead to medical-related death claims. We investigated eight cases of elderly fatality due to acute abdominal diseases in forensic autopsy cases. Although most fatalities were unwitnessed, possibly due to the characteristics of elderly individuals, recent social backgrounds, and involvement with health care, some cases of possible misdiagnosis suggested that physicians should carefully consider atypical clinical manifestations and the characteristics of elderly individuals when the managing abdominal symptoms, particularly in primary health care. Our investigation of these forensic autopsy cases indicated the particular importance of peritoneal adhesions as an unexpected cause of acute abdomen in the elderly due to strangulation ileus, even among those with no history of abdominal surgery or trauma. Diagnosis of acute stomach symptoms can be difficult in elderly patients. Pathophysiological examination and autopsy analyses can thus contribute to early-stage diagnosis and prevention of acute stomach symptoms in elderly patient populations.