The purpose of the present study was to identify risk factors for falls among institutionalized elderly, using the standardized risk assessment tool developed by Izumi. We examined 746 patients from three types of facilities: rehabilitation wards in four general hospitals, three long-term care facilities, and three nursing homes, for up to three months. The incidence of falls within all facilities was 12.5%. Patterns of relative risks of falling differed among types of facilities. The highest relative risk of fall in long-term care facilities and nursing homes was nurses' prediction, followed by history of fall and altered mentation. In contrast, that in general hospitals was mobility. In long-term care facilities, history of falls (odds 3.68, 95CI: 1.47-9.23) and interaction (history of falls and assistance with toileting) (odds 3.13, 95CI: 1.48-6.64) showed significance on adjusted-odds ratios for fall. History of falls, altered mentation, and assistance with toileting may be used to screen patients at a high risk for fall at admission.