In Japan, sudden death in the bathroom (what we call 'bath-related death') has been reported to occur particularly in the elderly population in the winter. This investigation aimed to obtain a better understanding of the factors associated with bath-related deaths. For this purpose, a retrospective review of the inquest records in Kagoshima Prefecture, the southwest part of Japan, during 2006-2007 was performed. There were 338 cases of bath-related death, which corresponds to a crude mortality rate of 9.7 per 100,000 persons per year. The occurrence of bath-related death was similar to that of other prefectures in Japan, despite the warm environment in Kagoshima. The victims' ages ranged from 37 to 101 years (mean 76.6 years) and 88.8% of patients were over 65 years. The associated factors included winter season (56.2%) and a medical history of hypertension (37.3%). These demographic and circumstantial factors correlated with previous studies in Japan. These results suggest that the Japanese method of bathing, in addition to cold bathrooms in winter, contributes to the high rate of bath-related death in Japan. In addition, the mortality rate of people who lived alone was significantly higher than that of those who lived with their families. Most cases occurred in the home bathroom (84.9%) at the time when elderly people usually bathe (48.7%). Our results indicate that bath-related death occurs most often during the normal daily life of the aged. Protective activities of the Japanese government and society should aim to reduce the number of these tragic deaths in the bathroom. Further, no autopsies were performed on the cases in this study. Therefore, the rate of autopsies in bath-related death should be increased in order to accumulate data based on objective evidence.