Public-key encryption with keyword search (PEKS) facilitates cloud servers in ciphertext and trapdoor matching without the need for decryption, safeguarding data privacy. Nevertheless, the prevailing schemes currently depend on bilinear pairings that are vulnerable to quantum computer attacks. Additionally, their dependence on Public Key Infrastructure (PKI) leads to a cumbersome and expensive process for managing certificates. On the other hand, lattice-based identity-based PEKS simplifies certificate management but encounters problems with key escrow. To tackle these issues, we propose a scheme for lattice-based certificateless PEKS. This scheme not only sidesteps the complexities of PKI but also fortifies security against quantum threats. It maintains indistinguishability under chosen plaintext attacks within the random oracle model and robustly defends against adversaries—whether they attempt to manipulate user public keys or obtain the system’s master key. Based on exhaustive theoretical and experimental analysis, we’ve shown that our scheme offers substantial efficiency improvements over existing solutions.