Abstract: To solve the problems of low efficiency and limited scenarios of privacy protection schemes such as zero-knowledge proof and secure multi-party computing, this paper focuses on the application of TEE in smart contract privacy protection. The basic concept, operation mechanism and trusted execution environment of smart contract were expounded. According to the operation mechanism of smart contract, the potential privacy threats of smart contract were summarized from three aspects: external data feeds, contract data and contract code. On this basis, the research scheme of using TEE to solve the privacy threat of smart contract was summarized. The possible research directions and future prospects of smart contract privacy were proposed.