A wireless communication apparatus that communicates between first and second wireless communication apparatuses. The second wireless communication apparatus includes a storage unit for storing group ID, a switch for giving instructions of setting up group ID, a transmission/reception unit for transmitting group ID read out from the storage unit to the first wireless communication apparatus to be put together in a group, and receiving a setting up completion signal transmitted from the first wireless communication apparatus, and a control unit for, reading out the group ID from the storage unit to send thus read out group ID to the transmission/reception unit when the switch is operated, and the control unit compares group ID transmitted from the first wireless communication apparatus and the group ID stored in the storage unit when the transmission/reception unit receives the setting up completion signal.