Abstract: The Web 3.0 digital economic system takes the blockchain platform as its infrastructure, and revolves around the digital assets such as cryptocurrencies, NFTs, digital collectibles, and decentralized applications (DApps) like decentralized finance (DeFi) and gaming finance (GameFi) to conduct various socio-economic activities. Smart contracts are the core of DApps on the public blockchains and the public permissioned blockchains, such as Ethereum, Solana, EOSIO, Findora, Antchain, ChainMaker, et al. Smart contracts can be deployed by any individual or organization, and are visible and accessible to all blockchain users. This openness brings new opportunities for economic development while also harboring numerous financial risks. We analyze potential risks for Web 3.0 digital economic by focusing on smart contract and summarize the current research on risk perception technology from three aspects: encoding, functionality, and application of smart contracts. We first introduce the research challenges, security vulnerability types, and four categories of vulnerability detection methods in smart contract vulnerability detection technology. Next, we analyze common types of smart contract scams and summarize existing scam recognition techniques based on different classifications of training data. Subsequently, we introduce the current state of technology for detecting four types of illicit transactions behaviors based on blockchain transaction records. Lastly, by analyzing the limitations of existing work, we envision the future research directions.