The invention discloses a homomorphic encryption method supporting ZKPs (zero knowledge proof) and a blockchain transaction amount encryption method, and belongs to the technical field of informationsecurity. The method comprises the following steps: generating a public key, a private key and system parameters according to a zero knowledge proof requirement and a Paillier algorithm; performing encrypting by using an encryption algorithm, the public key and the system parameters according to a given plaintext, and outputting ciphertext (E, c1, c2 and c3); and performing decrypting by using a decryption algorithm and the private key according to the given ciphertext, and outputting a plaintext. According to the method, the Paillier homomorphic algorithm is improved, the ciphertext of the four parts can be used for keeping the transaction amount secret on the whole, and the commitment part E can also be used for proving the zero knowledge range of the transaction amount, so that the Paillier algorithm is combined with the FO commitment-based zero knowledge range proving, and the range proving of the ciphertext is supported. Since the private key lambda is hidden in the system parameter k, each user has its own public and private key, the use is more convenient, and the security performance is better.