A Quality of Service, QoS, improvement method performed by a QoS decision network element, wherein the method comprises: • when a user equipment A and a user equipment B are attached to a mobile network, acquiring a user identity of the user equipment A and a user identity of the user equipment B that are sent by the mobile network; • receiving an IP address and a service port number of the user equipment A, and an IP address and a service port number of the user equipment B that are sent by a web real-time communication, WebRtc, server, after the WebRtc server receives a call request signaling sent by the user equipment A to the user equipment B; • binding the IP address and the service port number of the user equipment A, and the IP address and the service port number of the user equipment B to the user identity of the user equipment A and the user identity of the user equipment B, respectively, thereby establishing, for each of the user equipment A and user equipment B, a correspondence between the IP address, the service port number and the user identity; • receiving a service acceleration request sent by the user equipment A, wherein the service acceleration request comprises the user identity of the user equipment A and the user identity of the user equipment B and serves for requesting a QoS improvement on a service between the user equipment A and the user equipment B (302, 408, 510); • obtaining the IP address and the service port number of the user equipment A and the IP address and the service port number of the user equipment B based on the correspondence according to the user identity of the user equipment A and the user identity of the user equipment B; • forming a parameter according to the IP address and the service port number of the user equipment A and the IP address and the service port number of the user equipment B, and • sending a QoS improvement request to a policy and charging rule function entity, PCRF (411, 412, 511, 512). • when a user equipment A and a user equipment B are attached to a mobile network, acquiring a user identity of the user equipment A and a user identity of the user equipment B that are sent by the mobile network; • receiving an IP address and a service port number of the user equipment A, and an IP address and a service port number of the user equipment B that are sent by a web real-time communication, WebRtc, server, after the WebRtc server receives a call request signaling sent by the user equipment A to the user equipment B; • binding the IP address and the service port number of the user equipment A, and the IP address and the service port number of the user equipment B to the user identity of the user equipment A and the user identity of the user equipment B, respectively, thereby establishing, for each of the user equipment A and user equipment B, a correspondence between the IP address, the service port number and the user identity; • receiving a service acceleration request sent by the user equipment A, wherein the service acceleration request comprises the user identity of the user equipment A and the user identity of the user equipment B and serves for requesting a QoS improvement on a service between the user equipment A and the user equipment B (302, 408, 510); • obtaining the IP address and the service port number of the user equipment A and the IP address and the service port number of the user equipment B based on the correspondence according to the user identity of the user equipment A and the user identity of the user equipment B; • forming a parameter according to the IP address and the service port number of the user equipment A and the IP address and the service port number of the user equipment B, and • sending a QoS improvement request to a policy and charging rule function entity, PCRF (411, 412, 511, 512).