Method, device and system for using polymerizing maximal bit rate

The invention discloses a method for using a polymerizing maximal bit rate in order to enable a system to exactly control the AMBR, the performance of the system is optimized, and the utilization ratio of a network resource is increased. An AMBR controlling parameter corresponding to an AMBR controlling method is sent by gaining the AMBR controlling method of a non-GBR carrier between a UE and a PDN; and the AMBR performing functional body of the received AMBR controlling parameter performs resource dispatching for the current non-GBR carrier of the UE according to the AMBR controlling method. The invention also discloses an MME, the AMBR performing functional body and a mobile communication system.