Fecha de publicación: 20/02/2024 Fuente: Wipo "BigData" The invention provides a big data transaction privacy protection method and system in the technical field of big data transaction. The method comprises the following steps: step S10, a buyer client sends a test order purchase request to a seller client based on transaction information; step S20, the seller client selects a data sample, sends the data sample to the server and executes a data desensitization operation; step S30, the buyer client performs a fusion test on the data sample; step S40, the buyer client sends a big data purchase request to the seller client based on the transaction information; step S50, the seller client selects corresponding big data based on the big data purchase request, notarizes the big data through a block chain, adds a verification field in the big data, encrypts the verification field and sends the encrypted verification field to the server; and step S60, the server delivers the big data to the buyer client through a federated machine learning technology and a load balancing technology. The method has the advantages that the privacy protection capability and the trust construction efficiency of big data transaction are greatly improved.