A wireless terminal device (TA to TH) that performs wireless communication with the wireless terminal device (TA to TH) of another party via relay by a relay device or directly, comprising: communication permission request means for receiving a downlink signal that is transmitted from a pre registered specified relay device when requesting communication, specifying an idle channel based on idle channel information that is included in the downlink signal, and requesting communication permission from a relay device that provides the idle channel using the uplink frequency of the specified idle channel; and communication means that uses the same frequency as the frequency of the downlink signal from the specified relay device for transmitting a signal to the wireless communication terminal device of the other party requesting communication when it is not possible to receive the communication permission from the relay device from which the communication permission was previously requested, wherein the communication means comprises: response receiving means for receiving a response from the wireless terminal device (TA to TH) of the other party; determining means for determining whether or not the response comes directly from the wireless communication terminal device of the other party and not via a relay device; specification means for specifying a frequency that can be used when it is determined that the response is a direct response; and direct communication exchange means for setting the communication frequency to the specified useable frequency, and exchanging communication with the wireless communication terminal device of the other party. communication permission request means for receiving a downlink signal that is transmitted from a pre registered specified relay device when requesting communication, specifying an idle channel based on idle channel information that is included in the downlink signal, and requesting communication permission from a relay device that provides the idle channel using the uplink frequency of the specified idle channel; and communication means that uses the same frequency as the frequency of the downlink signal from the specified relay device for transmitting a signal to the wireless communication terminal device of the other party requesting communication when it is not possible to receive the communication permission from the relay device from which the communication permission was previously requested, wherein the communication means comprises: response receiving means for receiving a response from the wireless terminal device (TA to TH) of the other party; determining means for determining whether or not the response comes directly from the wireless communication terminal device of the other party and not via a relay device; specification means for specifying a frequency that can be used when it is determined that the response is a direct response; and direct communication exchange means for setting the communication frequency to the specified useable frequency, and exchanging communication with the wireless communication terminal device of the other party. response receiving means for receiving a response from the wireless terminal device (TA to TH) of the other party; determining means for determining whether or not the response comes directly from the wireless communication terminal device of the other party and not via a relay device; specification means for specifying a frequency that can be used when it is determined that the response is a direct response; and direct communication exchange means for setting the communication frequency to the specified useable frequency, and exchanging communication with the wireless communication terminal device of the other party.