In a cloud environment, ciphertext-policy attribute-based encryption (CP-ABE) plays an important role in attaining fine-grained data access control and confidentiality. In CP-ABE, since each attribute can be shared by a number of users and each user can maintain multiple attributes, the attribute will not be deleted for other users with the same attribute in practice, which may affect other users. Thus, how to revoke attributes is a significant and complex issue with CP-ABE schemes. To solve these issues, we present a novel CP-ABE with an efficient user or attribute revocation model. In this approach, the attribute revocation problem is effectively solved using the attribute group concept. The attribute controller (AC) in the proposed model updates the non-revoked user’s secret key if a user or attribute is revoked from the group. Besides, the proposed revocation model enhances security against cooperation between revoked and non-revoked users. Simulation results depict that the proposed revocation model attained better key update time, ciphertext update time, encryption time and decryption time.