Decryption method and system based on elliptic curve

The invention discloses a decryption method and system based on an elliptic curve, and belongs to the technical field of information security. The method comprises the following steps: sending a private key fragment and a ciphertext to a password device based on a terminal device; extracting a bit string from the ciphertext based on a cryptographic device, verifying whether the bit string satisfies an elliptic curve equation, and if so, performing auxiliary calculation on the private key segment and the ciphertext to obtain a calculation result of the auxiliary calculation; extracting a bit string from the ciphertext based on the terminal equipment, verifying whether the bit string meets an elliptic curve equation, if so, performing point multiplication on the calculation result of the auxiliary calculation, obtaining the calculation result of the point multiplication, and sending the calculation result of the point multiplication and the ciphertext to the password equipment; and decrypting the ciphertext acc