System and method of sending color ring in multimedia based on mobile communication network

The system comprises: core network elements (MSC Server,MGW,HLR) in WCDMA R4 mobile network and a MRBT (multimedia ring back tone) platform composed of SAN (signaling access node),AS (application server), MS (media server), DB (database) and server of portal website. The method thereof comprises: adding the ID of MRBT in called HLR; according to the ID and load type of MRBT, the calling MSV server /MGW routes the MRBT call to the home MRBT platform of the called party; the home MRBT platform plays back the MRBT to the calling party; after the called party is off hook, the MSC Server/MGW releases the load between the home MRBT platform of called party and itself; the load link between the calling and called parties is built by the calling and called MSC Server/MGW.