Abstract: Based on the four types of risks of Internet finance, this paper uses decision-making laboratory method (DEMATEL) and interpretative structural model (ISM) to study and analyze the risk prevention and control path of Internet finance, in order to explore the role of blockchain technology in the process of Internet risk prevention and control.The results show that :(1) solving Internet technical problems is the first step to prevent and control Internet financial risks of blockchain.(2) Prevention and control of Internet technical risks and legal supervision are the core of the sustainable development of the Internet financial industry.(3) Improving market credit regulation needs the support of technology and legal supervision.(4) The continuous improvement of business risks shall be based on the consideration of technology, law and transaction credit.The research results provide a set of application path system for the prevention and control of the risks of Internet finance with blockchain technology. It is hoped that more scholars can increase their attention to the prevention and control of the risks of blockchain and Internet finance, and propose a more complete prevention and control of the risk path system of Internet finance with blockchain technology.It is suggested that the central bank can jointly promote the application of blockchain technology in the Internet finance industry from multiple levels, including the government, financial institutions, Internet enterprises and users, so as to realize the sustainable development of the Internet finance industry.