921 Great Earthquake of September 21 in 1999, magnitude 7.3, was centered in Taiwn middle region. The natural hazards of great earthquake represent an exogenous factor of price effect in real estate market. These impacts are expected to be more significant in heavily damaged area. This study aims to analyze the change of real estate market structure during reconstruction process in Nan-tou City damaged by the 921 Great Earthquake and to show the factors influencing those change. The possible factors, such as damages by the earthquake, property attribute and their location points, which are encouraged to rebuild or obstructed local stores to open, are revealed. The air photos taken immediately after the earthquake were used to analyze the damaged area and the second hand data from the local government were also used to verify the field survey results. The topographic map and urban plan map in ArcView GIS format supported by the city government contribute to this on site surveying. The annual floor areas of construction data are used to find out the real estate market change in quantity. The reconstruction process recorded the path of the residential and commercial real estate built up. The discrimant model used to demonstrate the reasons of the reconstruction of the real estate structure in terms of the property attributes. The success of the real estate market depends on the mechanism of the land ownership reorganization, financing terms of the banking system and the comprehensive conditions of the infrastructure in the damaged area. This study can contribute to the current situation of the real estate market and find out some direction of the future market growth.