A wireless microphone communication system comprising: two or more controllers having LAN interfaces; one or more wireless microphones; and one or more receivers having LAN interfaces and being configured to receive a radio wave from a transmitter of a corresponding wireless microphone; wherein the one or more receivers are coupled to the two or more controllers on a LAN; each controller (22,24) is coupled to a corresponding display device (22b,24b); the one or more wireless microphones are configured to output information indicating battery power of the wireless microphone to the one or more receivers; each controller is configured to receive information from the one or more receivers, through the LAN, said information including (a) information related to at least one of a receiving field intensity level and an audio output level at the one or more receivers and (b) the information indicating the battery power of the one or more wireless microphones; each controller (22,24) is coupled to a corresponding input device (22a,24a); each controller is configured to receive character string information from its corresponding input device and send the character string information to another controller through the LAN; each controller is configured to display on its corresponding display device (22b,24b) a window including (a) receiver regions, each displaying the information received from the corresponding receiver, and (b) a character string region being displayed upon detection of abnormality or failure of the wireless microphone communication system and displaying an alarm message, the character string received from its corresponding input device and another character string sent by said another controller; wherein the abnormality or failure of the wireless microphone communication system includes at least one of (a) the battery power of the wireless microphone being recognized to be a predetermined threshold or less by the controller and (b) the receiving field intensity level being a predetermined value or less for a predetermined time period or more. two or more controllers having LAN interfaces; one or more wireless microphones; and one or more receivers having LAN interfaces and being configured to receive a radio wave from a transmitter of a corresponding wireless microphone; wherein the one or more receivers are coupled to the two or more controllers on a LAN; each controller (22,24) is coupled to a corresponding display device (22b,24b); the one or more wireless microphones are configured to output information indicating battery power of the wireless microphone to the one or more receivers; each controller is configured to receive information from the one or more receivers, through the LAN, said information including (a) information related to at least one of a receiving field intensity level and an audio output level at the one or more receivers and (b) the information indicating the battery power of the one or more wireless microphones; each controller (22,24) is coupled to a corresponding input device (22a,24a); each controller is configured to receive character string information from its corresponding input device and send the character string information to another controller through the LAN; each controller is configured to display on its corresponding display device (22b,24b) a window including (a) receiver regions, each displaying the information received from the corresponding receiver, and (b) a character string region being displayed upon detection of abnormality or failure of the wireless microphone communication system and displaying an alarm message, the character string received from its corresponding input device and another character string sent by said another controller; wherein the abnormality or failure of the wireless microphone communication system includes at least one of (a) the battery power of the wireless microphone being recognized to be a predetermined threshold or less by the controller and (b) the receiving field intensity level being a predetermined value or less for a predetermined time period or more.