A channel switching method, a channel switching device, and a channel switching system are provided. The method includes that: a network buffer apparatus determines whether a buffered video stream burst in unicast is synchronous with a channel video stream pushed by a network node to a client in multicast; notifies the client of sending a request for joining a multicast group, so as to implement fast channel switching; and dynamically adjusts the speed of pushing the video stream in unicast, so that the number of concurrent connections of the client and the channel switching efficiency are increased, and the deployment and operation cost of an Internet Protocol Television (IPTV) system is decreased. In this case, the channel switching scheme achieves universality and expandability, and the level of user experience is improved.