Abstract: In today's widely-used cloud computing, the mode of completing data processing by the cloud improves the user's ability to process data, but it also brings the risk of privacy data leakage. Fully homomorphic encryption is an emerging research topic. It supports the calculation of ciphertext when the private key is unknown. The decryption of the result is equal to the result of the corresponding plaintext calculation, which is helpful to solve the leakage of user privacy data in cloud computing. In response to a homomorphic encryption scheme based on the RLWR problem proposed by Luo et al. in 2019, we improve this scheme by combining the ciphertext batch technology, and the number of plaintexts that can be encrypted is N times that of the original scheme.