Based on full IP core network architecture

commercialized IP Multimedia Subsystem（IMS） provides high QoS to the users

which relies to a large extent on the IP backbone network.Integrated Generalized Multiprotocol Label Switching（GMPLS） is the core technology for the next generation backbone network.Using traffic engineering technology

it provides high QoS.This paper expounds the realization of high QoS of IMS by using GMPLS and analyses the realization methods.