Fuente: Wipo "IOT" The purpose of the present invention is to implement a mechanism capable of automatically linking money value with IoT data, and to provide a data transaction system for IoT data. This data transaction system is an IoT data transaction system, and is provided with: a data transmission unit capable of transmitting data to a predetermined object; a data transaction unit that executes a transaction contract of the data; and an IoT device that provides IoT data, in which the data transaction unit instructs the data transmission unit to transmit the IoT data from the IoT device to a data provider having an account that has issued a purchase delivery disk on the basis of the purchase delivery disk of the IoT data issued by a prescribed account and the sales delivery disk issued by the account of the IoT device, and transmits the IoT data from the data transmission unit to the data provider having the account that has issued the purchase delivery disk on the basis of the sales delivery disk issued by the account of the IoT device. And paying the money value of the sent IoT data to an account of the IoT device.