The invention discloses a blockchain state storage method based on an SQL database. By the adoption of the method, when a blockchain is initialized, a database is generated, a plurality of data sheets can be built by each contract, creating, reading, updating, deleting operations based on SQL grammar can be conducted on sheet structures and sheet data by contracts, and some interfaces with permission are encapsulated to be called by other accounts. A database change log (log) is generated by nodes after each transaction is highly executed, and the log is used as hash depository receipt, wherein a world state continuously proceeds to ensure the accordance of each node data. According to the method, the present situation that only simple data structures can be stored in blockchains is changed, a data sheet structure used widely is adopted, the creating, reading, updating, deleting operations are supported, even a cross-contract conjunctive query is carried out, the functions which intelligent contracts on the blockchain can perform are enriched, and at the same time, the docking difficulty of systems out of blockchain is reduced.