The present invention provides a repeater, a wireless communication system, a control method and a recording medium that can transmit the same signal received by plural repeaters to the recipient wireless communication device without redundancy of the signal. A repeater connected to a network and relaying a communication of a wireless communication device comprises a packet reception unit receiving a packet transmitted from a sender wireless communication device to a recipient wireless communication device from the network or the sender wireless communication device, a transmission unit transmitting the packet received by the packet reception unit to the recipient wireless communication device, a packet storing unit storing the packet to be transmitted to the recipient wireless communication device as a first packet, and a packet selection unit comparing the first packet with a second packet other than the first packet, and discarding the second packet when both packets match under a predetermined condition.