The invention provides a credible privacy intelligent service computing
system based on a block chain, which performs computing service,
encryption service and credible right and interest service, andcomprises a user end, a model providing end and a
cloud server end , the user side is a user of service computing and is provided with a data and public and private
key generator, and the user end puts forward demand and request service and starts the whole
service process after authority is obtained; the model providing end obtains the encrypted public key from the
cloud server end, encrypts thetrained prediction model by using the public key, provides the encrypted prediction model to the
cloud server end, provides a classification
label at the same time, and obtains a rights and interestsdistribution result and corresponding cost after the calculation service is completed; and the cloud
server end is used for providing computing resources and model services and completing the requestof the user end. The invention further provides a calculation method and a calculation model, a
homomorphic encryption method is adopted, and the calculation model comprises a credible privacy service calculation sub-model, a prediction service privacy calculation sub-model and a prediction service rights and interests evaluation sub-model.