To lower communication complexity, a Certificateless homomorphic encryption(CLHE) scheme based on the Learning with errors(LWE) problem is constructed by introducing a new technique called probabilistic encoding with weakly homomorphic property. This technique can conveniently convert an intended message into two elements in a ring, which will be respectively encrypted under both public keys of a user in certificateless cryptosystem.Upon knowing both elements simultaneously, the original message can be easily recovered. It is hidden perfectly by the probabilistic property of encoding. This CLHE removes evaluation keys by using the approximate eigenvector method given by Gentry et al., which makes it into a pure CLHE. It is proven to be semantic secure in the Random oracle model(ROM). The results indicate it is able to homomorphically evaluate any functions in a class functions with given multiplicative depth L. To lower communication complexity, a Certificateless homomorphic encryption (CLHE) scheme based on the Learning with errors (LWE) problem is constructed by introducing a new technique called probabilistic encoding with weakly homomorphic property. This technique can conveniently convert an intended message into two elements in It is hidden perfectly by the probabilistic property of encoding. This CLHE removes evaluation keys by using the approximate eigenvector method given by Gentry et al., which makes it into a pure CLHE. It is proven to be semantic secure in the Random oracle model (ROM). The results indicate it able to homomorphically evaluate any functions in a class functions with given multiplicative depth L.