Wang Xiaoxia (Songliao Water Resources Commission, Heilongjiang Upper Reaches Hydrology and Water Resources Center, Heilongjiang Heihe 164300) Abstract: In the operation and management of public institutions, establishing an effective internal control system is of great significance for their stable development. Currently, some public institutions face issues such as insufficient risk assessment and early warning mechanisms, incomplete internal control system construction, inadequate information communication and sharing, and lack of supervision and evaluation mechanisms. To address these challenges, it is particularly necessary to strengthen the construction of internal control systems from a risk prevention perspective. This requires optimizing risk assessment and early warning mechanisms, correctly identifying and proactively responding to risks; constructing a comprehensive internal control system to standardize various business processes; improving information communication and sharing levels to ensure timely and accurate information dissemination; and establishing sound supervision and evaluation systems to ensure effective implementation of internal controls. Through these measures, the safety and rational use of funds in public institutions can be guaranteed, financial management levels can be enhanced, risk prevention capabilities can be strengthened, and public institutions can be supported in entering a track of high-quality development. This paper systematically studies the construction of internal control systems based on risk prevention in public institutions, aiming to provide references for relevant institutions. Keywords: public institutions; internal control; risk prevention; financial internal control