Cloud storage services employ multi-authority attribute-based encryption (MA-ABE) with policy hiding extensively. However, in the existing MA-ABE schemes with policy hiding, all attributes are managed by a centralized authority (CA), which is also responsible for providing the user with the partial attribute keys needed for decryption. Thus, by calculating the required secret keys, CA may decrypt any ciphertext present in the cloud system. Moreover, it will increase the security risk of encrypted data in cloud. This paper proposes a decentralized multi-authority ciphertext-policy attribute-based encryption scheme that supports policy hiding. Participation in the proposed scheme does not require the centralized authority (CA), but rather numerous attribute authorities (AAS). Every AA manages several attribute sets and offers attribute keys for data users. In the encryption computation and key generation phase, we add an exponential operation to better protect the user’s sensitive data. Our scheme outperforms the current schemes in terms of functionality, as demonstrated by the performance analysis. Furthermore, the standard model has demonstrated the full security of our scheme.