Disclosed is a wireless relay device wherein the number of stream multiplexes between a wireless transmission device and a wireless reception device can be increased without increasing the number of antennas for the wireless transmission device or the number of antennas for the wireless reception device. Specifically disclosed is a wireless relay device (100) for relaying and transmitting a signal between a wireless transmission device and a wireless reception device, which has Nrelay number (Nrelay is a natural number of 2 or more) of antenna ports, wherein a diversity reception unit (106) diversity-receives the signal which is transmitted from the wireless transmission device, and which has been modulated by the modulation multi-value number of M (where M=Nrelay 2) via the Nrelay number of antenna ports, a stream generating unit (112) divides the signal so as to generate Nrelay pieces of streams, modulation units ((114-1) to (114-Nrelay)) QPSK-modulate the Nrelay pieces of streams, and transmission RF units ((115-1) to (115-Nrelay)) transmit the N pieces of streams after modulation to the wireless reception device via the Nrelay number of antenna ports.