Abstract: In cloud computing environments, equality test can effectively address the challenge of comparing whether two ciphertexts are encrypted under the same plaintext without decryption. Among existing schemes, identity-based encryption with equality test (IBEET) significantly simplifies certificate management compared with traditional public-key encryption schemes, demonstrating considerable value. While China’s independently developed SM9 encryption algorithm has been successfully selected as an ISO/IEC international standard, existing SM9-based equality test schemes generally remain vulnerable to subversion attacks. Specifically, by subverting the randomness generation process, an adversary in possession of a backdoor key can recover the plaintext, thereby compromising the security of the scheme. To address this issue, an RCCA (relaxed chosen-ciphertext attack) secure identity-based SM9 encryption scheme with equality test (RCCA-SM9-IBEET) was proposed. The scheme employs cryptographic reverse firewalls (CRF) to re-randomize the inputs and outputs of potentially compromised users, thereby resisting subversion attacks. Furthermore, we define the concept of OW-ID-RCCA (one-way chosen-ciphertext security against a relaxed chosen identity attack) security model, which supports ciphertext re-randomization for compatibility with the reverse firewalls. A rigorous security proof is provided in the random oracle model. Finally, we analyze the computational and communication costs of the proposed scheme from both theoretical and experimental perspectives.