Threshold Cryptography (TC) is a security technique that divides a secret into multiple pieces, with the original secret only being recoverable when a certain minimum number of these pieces are combined together. This approach boosts security by preventing a single point of failure. In blockchain technology, applying TC enhances security by spreading out cryptographic key management responsibilities, thus reducing vulnerability to attacks. To further strengthen blockchain systems, we propose Threshold cryptography using smart contract. Smart contract can ensure accurate execution of the protocol and allow participation from random users, incentivizing honest behavior. The TC protocol integrates generateProof and reconstructSecret protocol functions based on zk-STARKs, a technology that cut down transaction costs and remove the processing tasks off-chain. With this setup, smart contracts only verify computation accuracy, lightening the load on the blockchain network.