An Internet Protocol Television (IP-TV) broadcasting service system and method using a physical layer multicast switch are provided. The system comprises: a head end which converts an Ethernet signal to a virtual concatenation group (VCG) signal of a synchronous digital hierarchy/synchronous optical network (SDH/SONET); a multicast switch which multicasts the VCG signal in a physical layer; and a tail end which receives the multicasted VCG signal through a Synchronous Transmission Module level n (STM-N) optical link and restores the VCG signal to the Ethernet signal. Therefore, high quality TV broadcasting can be provided in an IP multicast network.