The embodiments of the present disclosure provide a private data processing method, a device and a medium, and relate to data security technologies. The method includes: initiating a user request to an intermediate server according to an input of a user to request the intermediate server to perform intermediate business processing according to the user request and to initiate a target business processing request to a business server; obtaining business result data encrypted with an account key of the user and fed back by the business server based on the target business processing request from the intermediate server; and using the account key of the user to decrypt the encrypted business result data.