Abstract: Disclosed is an image data communication apparatus for achieving real-time transmission of image data such as one compatible with an extended definition television using a plurality of communication lines having a transmission capacity equivalent to an ADSL system at a time. The data communication apparatus includes a data transmission section 10, gates AG and BG, and a data reception section 20. The data transmission section 10 packetizes original image data to be transmitted and assigns, to each packet 12, identification information 14 by which one packet can be distinguished from another so as to output generated packets. The gates AG and BG refer to the identification information 14 to distribute the packets output from the data transmission section 10 to different communication lines AN and BN based on previously set conditions.