The invention relates to a method for realizing multimedia fusion service based on intermediate part, wherein said method comprises that: a, application register that obtaining and storing the application description document registered via application server and the distribution strategy of said application description document; b, service generation that selecting needed application and finding relative distribution relation, the transmission between application servers, and the treatment of abnormal state, and using the format of service description document to store generated service; c, service execution that reading service description document of service executing engine, analyzing the service logic define in service description document, reading the first application met execute document, transmitting the interface parameter, and distributing application server to server; based on the result, confirming the application of next execution until end. Said system comprises application register device, service generator and service executer.