A method of delivering media data in a hybrid network capable of providing broadcasting and interne communication together is provided. The method includes generating a Media Processing Unit (MPU) to process media data, and delivering the generated MPU, wherein the MPU includes an MPEG Media Transport (MMT) Processing Unit (MMPU) box including information on the MPU, a Media Data box (MDAT) including one or more media data fragments which are generated from the media data, and an MMFU box including information on each media data fragment.