The invention provides an Internet of things data management method, platform and device. The method comprises the following steps: a data layer receives the Internet of Things data sent by a terminaldevice and writes the Internet of Things data into a blockchain, wherein each node of the blockchain network comprises a member and a data layer in an application management layer; the data layer receives first tradable data information sent by a first member, and broadcasts the tradable data information to the blockchain network, so that each node of the blockchain network confirms the first tradable data information; if the blockchain network confirms that the tradable data information is legal, the data layer writes the tradable data information into the blockchain, so that a second membersends a transaction request to the first member according to the tradable data information. According to the method, the platform and the device in the invention, the Internet of Things data are stored based on the blockchain technology, and the Internet of Things data can be managed and supervised effectively.