Disclosed is a data distribution apparatus delivering multicast data to a terminal belonging to a multicast group, including: a table generating unit to generate a table including a source address (SA) of the terminal and a destination address (DA) for requesting the multicast data in association with port information of the terminal; an address discrimination unit to discriminate a combination of DA and SA contained in the multicast data; a forwarding destination information generation unit to generate forwarding destination information designating a forwarding destination of the multicast data by obtaining the port information in the table, corresponding to the discriminated combination, and inserts the forwarding destination information in the multicast data for transfer to a L2 switch; and a port selection unit provided in the L2 switch to select port to transfer the multicast data referring to the forwarding destination information and a routing table provided in the L2 switch.