Cross sectional studies were conducted in five towns in Japan before and after the introduction of the Long-term Care Insurance System (LTCIS), in order to evaluate the factors relating to depression among family caregivers for the frail elderly. Depressive caregivers were more likely to consult with their doctors, to be in poor health, to care for demented elderly with behavioral disturbances than the non-depressive caregivers both before and after the LTCIS. Before LTCIS, depressive caregivers were more likely to attend to the elderly for more than 16 hours per day than their counterparts. After the LTCIS, depressive caregivers were more likely to be a spouse, to care for a frail elderly male, and less likely to be able to go out without accompanying the elderly than their counterparts. Even after the introduction of LTCIS, half of the caregivers were depressive. It is suggested that a government agency should be created to support not only the frail elderly but also their caregivers.