The invention relates to a method for encapsulation of media data stream in a multimedia broadcasting system, and the media data stream of each channel of the broadcasting system selectively comprises video frequency components, audio frequency components and accessory data components, which comprises the following steps: choosing and encapsulating one or more components among the video frequencycomponents, audio frequency components or accessory data components in need of sending in the data frame of each channel; settling the data and parameters of the selected data components; collocatingthe header and recording the length of the header therein; recording the symbol information and the parameter information of the selected data component type in the header. The method sends multi-media data stream effectively in a channel via the encapsulation components, and sends only the components in need of sending and correspondingly transferring the component broadcasting program needed inthe mobile terminal via the component symbols, which can enhance the sending efficiency, save the mobile terminal power supply and better satisfy the demands of mobile multimedia industry.