The invention relates to a privacy protection method based on trusted third party attribute fuzzy grouping under the cloud environment. The method comprises an attribute fuzzy grouping access control method and an interaction protocol based on trusted third party protection, and is mainly used for three stages of cloud user registration, cloud end data creation and cloud end data access, and the stages support direct interaction and indirect interaction. Through the access control method based on attribute fuzzy grouping, conversion of an access entity, an access control policy and user requests is achieved on the three stages by the trusted third party, leakage of privacy information of users can be effectively avoided, and authenticity of anonymous access users is ensured. Through the interaction protocol based on trusted third party protection, interaction behaviors of the user, the trusted third party and the cloud service party are stipulated, data encryption, timestamp and other technological means are added to the protocol, and safety of user data, user identities and attribute privacy is guaranteed in the interaction process of the user, the trusted third party and the cloud service party.