Abstract: A personal multimedia on-line broadcasting system is provided, comprising: a network broadcasting server including a plurality of media sources, a network interface card, and a network broadcasting server module; and a client device including a network interface card, a video and audio output interface, and a client player module. The operation of the network broadcasting server module is controlled by a software application program to execute the following procedures: receiving a request from a client device, determining a broadcasting bandwidth, processing the streaming data of a video and audio signal, and broadcasting the streaming data to the client device according to the broadcasting bandwidth.