The invention provides a quality of service renegotiation method in order to solve the technical problems so that a DRNC can span an Iur interface to trigger Qos renegotiation. The method comprises that: in the process that UE establishes service, an SRNC records Qos negotiation information designated by a CN; when the UE in a cell administered by the DRNC establishes a wireless link or newly establishes service on a wireless link of the existing Iur interface, the SRNC sends the Qos negotiation information of the service to the DRNC; when the DRNC discovers that the cell of the wireless link is over-loaded or has congested resources and needs to adjust the resource occupied by the service, the DRNC reselects a Qos negotiation parameter according to the recorded Qos negotiation information, and informs the SRNC of the reselected Qos negotiation parameter; and after receiving the Qos negotiation parameter sent by the DRNC, the SRNC initiates a Qos renegotiation flow to the CN.