Data sharing method based on block chain

The invention is suitable for the technical field of data sharing, and provides a block chain-based data sharing method, which comprises the following steps of: adjusting new data according to existing shared data to obtain new shared data; calculating a scarcity score and a sensitivity score according to the new shared data, and calculating the scarcity score and the sensitivity score according to the existing shared data; clustering based on the scarcity score and the sensitivity score of the new shared data and the scarcity score and the sensitivity score of the existing shared data to obtain a target cluster; determining reference shared data of the target cluster, and calculating a relative contribution coefficient of new shared data based on a scarcity score and a sensitivity score of the reference shared data; determining an additional duration level based on the relative contribution coefficient, and calculating an access permission duration according to the additional duration level; and controlling