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In the traditional ciphertext-policy attribute-based encryption (CP-ABE) scheme,the access policy exists together with the ciphertext.This may leak the privacy of the data owner and bring potential security risks to the data owner in medicalscena-rios Therefore,solutions supporting access policy hiding have been proposed.However,most solutions need to generate redundant ciphertexts or key components in the process of implementing the decryption test,which increases the computing overhead of data owners and the storage overhead of data users.At the same time,malicious users may be motivated by its own interest to reveal their decryption keys.In order to solve the problems above,a lightweight medical data sharing scheme with access policy hiding and key tracking is proposed.Firstly,part of the master key is stored in the Enclave in advance by using software guard extensions(SGX) technology,so that the test results can be calculated accurately and quickly,and the generation of redundant ciphertexts and key components are avoided.Then,verifiable outsourcing technology is employed to reduce user's computing overhead,ensuring the correctness and completeness of decryption result.Finally,key tracking is realized by embedding the identity identifier in the decryption key of the data user.Performance analysis shows that the proposed scheme has certain advantages in terms of function and computing.The security analysis proves that the proposed scheme is secure under the selected plaintext attack.