In 2019, the National Development and Reform Commission led the issuance of a notice to promote the construction of the national “Xinyi Loan” platform. Since then, the national “Xinyi Loan” platform has entered the vision of SMEs. The difficult and expensive financing of SMEs has always been an important factor causing the low business environment indicators in China. The emergence of the national “Xinyi Loan” platform has well alleviated this problem. However, all the links in the platform are scattered and the information is isolated, and a long-term integrated mechanism has not yet been formed, so it cannot effectively prevent and control risks at present. By constructing a three-party incomplete information dynamic game model of the government, SMEs and financial institutions in the platform, this paper analyzes that all parties should strengthen the pre-loan investigation, in-loan management and post-loan default recovery of the “letter and easy loan” business. To create a good business environment and improve the integration of risk prevention and control, we should further strengthen substantive review, break information islands, promote diversified governance, update data in real time, increase punishment, and improve credit repair.