Global evaluation index acquisition method of federated learning system and federated learning system

The invention provides a global evaluation index acquisition method of a federated learning system and the federated learning system. Every two participants of the federated learning system trade one secret random number. And each participant generates an interference coefficient according to all secret random numbers of the participant, and encrypts the local confusion matrix by using the interference coefficient to obtain an encrypted local confusion matrix. The method comprises the following steps: acquiring encrypted confusion matrixes of all participants at a central server and aggregating the encrypted confusion matrixes, and offsetting interference coefficients in the encrypted local confusion matrixes during aggregation, so as to obtain a global confusion matrix; in the embodiment of the invention, the participants send the encrypted local confusion matrixes to the central server, and meanwhile, the central server does not decrypt each encrypted local confusion matrix, so that sensitive information su