Indonesia is a country with 129 active and 500 inactive volcanoes. Disasters caused by volcanic eruptions have impacted on several sectors including education. Development of geographic information system for mapping disaster-prone areas (KRB) can facilitate the identification of schools that require particular attention when disasters such as volcanic eruptions occur. This research aims to develop a web-based geographic information system for school mapping and disaster mitigation (SIMBAK). SIMBAK can map the schools located in the KRB, present school profile information and display the navigation. After SIMBAK have developed, the test was directed in two stages: limited test and expanded test to confirm the feasibility of a SIMBAK. Limited test completed by information system experts and disaster substance experts. Results from a limited test show a percentage value of 86.3%. The expanded test completed by actors involved in SIMBAK namely administrators, school operators, and users. The results of the expanded test show the percentage of the value of 87.9%. It means that SIMBAK is feasible to apply in areas that are in disaster-affected.