This paper first presents a Deep Packet Inspection（DPI）-based smart gateway service QoS guarantee and bandwidth speeding-up scheme.Then it elaborates the DPI status of the smart gateway

by which it identifies the high-priority user services

realizes QoS guarantee by adopting an absolute priority strategy;timely finds out user bandwidth bottles using the bandwidth detection mechanism of DPI;realizes real-time bandwidth speeding-up in cooperation with the portal push function of the smart gateway and the telecommunication operator platform and elevates telecommunication user experience perspective by implementing high priority-user service guarantee and real-time bandwidth speeding-up.