In order to solve the problem of data integration and sharing in heterogeneous databases, a heterogeneous database integration and transformation scheme based on Agent and XML is proposed. This model utilizes XML technology to construct a middleware between the client and database server, using mobile agents as the logical model framework to handle the autonomy and distribution issues of member systems in multi database systems. Then, the communication problem in the middleware system is solved by encapsulating the sent KQML message into an XML format document. The system testing results demonstrate that each Agent in this method can independently complete their own functions and cooperate with each other, which effectively solves the problem of intelligent integration of local database data, and it also has good adaptability to complex network environments.