The invention discloses a hierarchical classification access authorization management method based on roles. The hierarchical classification access authorization management method includes the following steps: S1, initialization is carried out, wherein it is assumed that n+1 data classes and m users exist in an assumed information system, an encryption key hierarchical tree is built, and calculation indexing is carried out on a main encryption key Kj and a class encryption key Kx; S2, data encryption is carried out; S3, user registration is carried out; S4, access requesting is proposed; S5, decryption is carried out. According to the hierarchical classification access authorization management method, a hierarchical classification authorization module based on the roles is built, a hierarchical encryption key management scheme based on the roles is used in the model, and permissions of the users for accessing specific data are given according to the roles and the grades of the users, so that the aim of more-fine-grained access control is achieved, the problem of unauthorized accesses caused by weak identity authentication is effectively solved, and meanwhile, the privacy of information resource in the system is effectively protected; in addition, the invention further provides an intermediate node for hiding hierarchical data structures in the system through access paths invisible to the users, and the leakage of sensitive information in the system is further prevented.