The pandemic of the new coronavirus infection from 2019 (COVID19) forced welfare facilities to implement infection prevention measures. The purpose of this report is to describe a case of infection prevention measures against COVID19 implemented by a social welfare corporation in Japan. The social welfare corporation established an infection control headquarters to manage the multiple welfare facilities and related facilities comprehensively. Then it proceeded to create manuals for daily infection control measures, to conduct training, to create a flow diagram for infection prevention of COVID19 in the facilities, to establish simple negative pressure ventilation equipment, and to set zoning of the facilities. These lessons are meaningful for other welfare facilities to prevent the outbreak.