Summary: This paper proposes a real-time disaster situation mapping system for campuses. University campuses have various features and issues (e.g., difficult to determine the number of people on campus at any one time as there are many students studying at the library or in their rooms, visitors can also use the open spaces, building layouts are often very complicated etc.), and therefore unique disaster prevention efforts are required. In order to address these prevention issues, a system that facilitates disaster situation information transmission by users will be effective. PlaceEngine is implemented for this system to allow users to estimate the current location easily by utilizing Wi-Fi devices.