Abstract
　On June 3, a pyroclastic flow in the Mizunashi River hit residential areas and killed 43 people. Shimabara City Government and Fukae Town Government decided to force the inhabitants to evacuate from the dangerous areas. The period of the evacuation was prolonged many times and more than ten thousand inhabitants were obligated to stay in the temporary dwelling for a long time without their ordinary works. Roads and railway within off-limit area were closed. The long-term volcanic activity rendered severe bad effects on the local economy in commerce and industry sightseeing, and agriculture. Local governments made efforts to support the evacuees considering the prolonged volcanic activity.
　In this paper, lengthening, widening and reducing of the evacuation zones after off-limits placed in Unzen eruption, administration of evacuation zones, monitoring and warning system, damage by suspension of traffic are reported from records of local governments and results obtained by interviews. Local government's risk management and the relief policy for evacuees are discussed.

【キーワード】：噴火，火砕流，警戒区域，危機管理，被災者対策
Key words: eruption, pyroclastic flow, off-limit zone, risk management, relief for evacuee

*長崎大学工学部社会開発工学科
Department of Civil Engineering, Faculty of Engineering, Nagasaki University