Abstract: A multimedia broadcast system and method supporting peer-to-peer (P2P) coordinated code conversion are provided. The method includes forming, by a data source device, one or more data segments from multimedia data, and then scattering the data segments to a P2P network formed by the viewers; wherein an individual P2P device is connected with one or more P2P devices via a network system to form a partner group, and then acquires code conversion degrees of each data segment to serve as a basis for strategically adjusting the coordinated code conversion of said multimedia data. The coordinated code conversion mechanism is supported by common P2P multimedia broadcast systems, and is capable of rapidly converting the multimedia data in one format into multimedia data in other different media formats, thereby enabling real-time broadcasting of data in different formats to clients using P2P networks of various specifications.