An object of the invention is to improve the reliability of a wireless control network management system. Gateway devices for relaying data communication between a monitoring/controlling host connected thereto via a wired network and a plurality of wireless nodes connected thereto via wireless circuit and constituting a wireless network, wherein the gateway device comprises wireless communication means for sending data from the host to at least any one of the wireless nodes, and redirect means for causing the wireless communication means to send the data to one of the wireless nodes and to transfer the data to the other gateway device connected to the wired network.