According to one embodiment of the present invention, a method for transmitting an IPTV streaming service by P2P transmission comprises the steps of collecting TS packets of n skipped units to generate an encapsulation unit for an IPTV streaming service (where n is a natural number); adding an extension header containing type information to the generated encapsulation unit (wherein, said type information is information for identifying the sequence of the encapsulation unit, which is required for decoding the IPTV streaming service); adding an IP header to the encapsulation unit to which the extension header containing the type information is added, in order to generate an IP packet; and transmitting the generated IP packet to at least one super peers.