The invention aims to protect content copyright and reduce the load on a stream server device in a stream distribution system having the stream server device, which stores bitstreams that include contents and control information necessary for image playback of contents, a plurality of terminal devices that playback received bitstreams, and a cache server device that mediates between these devices. A header separation unit in the stream server device separates header information, which is control information, from a bitstream stored in a storage unit. A data transmitting unit transmits the bitstream from which header information has been removed to the cache server device before a predetermined time, and transmits the header information to the cache server device at the predetermined time. The cache server device transmits a bitstream that combines the bitstream, which was received first, and the header information, which was received later, to a terminal device. The terminal device receives the bitstream at the predetermined time, and plays the content.