Fuente: Wipo "IOT" Disclosed are an external IoT data feeding method in a smart contract to form a reliable Oracle structure used in a smart contract and an Oracle system for the same. According to one embodiment of the present invention, the oracle system for feeding external IoT data in a smart contract of a blockchain comprises: an administrator managing an IoT device and an IoT gateway and implementing an access control list for IoT data generated by the IoT device as a smart contract to store the smart contract in a blockchain; a data storage receiving the IoT data from the IoT gateway in an off-chain and storing the received IoT data; a service provider requesting permission for use of the IoT data to the administrator; and an Oracle node receiving a grant to access the data storage by the administrator, receiving the IoT data from the data storage in response to the request when the service provider requests the data, and providing the IoT data. COPYRIGHT KIPO 2022