This study evaluates the prognostic factors and causes associated with mortality in Chinese diabetic patients after lower extremity amputations. Medical records of all diabetic patients admitted to the National Taiwan University Hospital for leg amputations from 1982 to 1991 were reviewed. Demographic data, medical history, amputation levels and admission routines, including fasting plasma glucose, cholesterol, triglycerides, blood urea nitrogen, creatinine, urine protein and electrocardiograms, and bacterial culture done during the admission period were recorded. The vital status of the patients was followed by personal contact and mortality was ascertained from government computer records. The causes of death were recorded according to the death certificates. Univariate analysis and multivariate Cox's proportional hazards model were used to identify the prognostic factors associated with mortality. A total of 87 diabetic amputees, of whom 34 died, were found within this 10-year period. Cerebral infarction, infection and diabetes mellitus were the most commonly reported causes of death. Their calculated mortality was 5.95 times higher than the mortality rate of the age-comparable population in Taiwan. A history of hypertension and coronary heart disease were found to be the best indicators for predicting a fatal outcome with rate ratios of over two-fold. This study shows that post-amputational mortality is high in diabetic patients and that the major cause of death is cerebral infarction. The major cause of death in this study differs from that reported for Caucasians, for whom cardiovascular disease is the most important cause of death.