To enhance the efficiency of surfing the Internet, an integrated platform for real estate agency is established based on service-oriented architecture (SOA). It employs the concept of search engine and loads the information provided by each real estate agency to this platform. Due to various types of data structure from each real estate agency website, a unified format must be defined for integrating the information. In this paper, the format is defined by XML and used to integrate heterogeneous database. Also, the format includes the data fields the agency websites required. It is processed in the platform which is expandable by receiving information from other sources in the future. In consideration of the copyright regulation, the agents are allowed to login and to share specific information on this platform in order to increase the transaction rate. The system also includes a Google Map engine for GIS service that marks the spatial location as users send the requests. It helps users to find the demanded housing information and retrieve the nearby geographic location.