A relay device includes a receiver that receives a wireless signal and outputs the received signal; a regenerator that restores original data from the received signal, and generates a regeneration signal from the original data; a non-regenerator that generates, using the received signal, a non-regeneration signal; a switching controller that selects and outputs the non-regeneration signal when the received signal is a multicast signal, and that selects and outputs the regeneration signal when the received signal is a unicast signal; and a transmitter that transmits a signal output from the switching controller as a transmission signal.