Purpose: This study aimed to investigate the changes in the placement and role of public health nurses (PHNs) following the introduction of the Long-term Care Insurance System in 2000, and its impact on health services and future national-policy regarding PHN activities. Methods: Questionnaires were sent to the directors for elderly healthcare services in 1,344 municipalities throughout Japan (all cities and 23 wards in Tokyo; a quarter of towns/villages) shortly after the enforcement of the Long-term Care Insurance System, in February and March of 2001. The survey instrument included items on population, the number of PHNs, and involvement of PHNs in elderly healthcare and preventive approach for the Long-term Care. Results: The response rate was 42.3% (569 municipalities). Eighty percent of the municipalities experienced no change in the number of PHNs in the healthcare division after the introduction the System. Transfer of PHNs to the Long-term Care Insurance division was a factor contributing to the reduction of PHNs in the healthcare division. Reevaluation of services had led to decreases in services unique to PHNs, such as home visits and community based rehabilitation. We found minimal impact on health education and consultation, the level of impact differed by type of service. Although PHNs were involved in preventive care in 70-80% of the municipalities, they had little involvement with evaluation of services when compared to planning and management. Conclusion: The epoch-making system reform triggered by the introduction of the Long-term Care Insurance System has produced rapid service changes in the welfare and outsourcing and also effected on the decrease of PHNs' home visits, which are unique to the profession.