<p>A method, an apparatus and a system for channel switching are provided by embodiments of the present invention. The method comprises: recording in real time a time stamp of the media message of a multicast media stream entering a cache and a key frame entering the cache; when a channel switching request sent by a terminal is monitored, acquiring a first time stamp of the media message entering the cache of a target channel at the channel switching request moment and a second time stamp of the media message in which the last key frame entering the cache is positioned of the target channel before the channel switching request moment; determining the time stamp difference between the first time stamp and the second time stamp; transmitting the time stamp difference and a burst media stream of the target channel to the terminal; and utilizing the time stamp difference to enable the terminal to correct the time stamp of the media message of the media stream received after the channel switching request moment. The embodiments of the present invention can reduce the delay for the terminal to broadcast multicast media streams, and enable the terminal which carry out channel switching and the terminal which does not carry out channel switching to broadcast multicast media streams synchronously.</p>
