Against the backdrop of the Double Reduction Policy, new trends have emerged in Chinese students’ overseas study choices. This study designed and implemented a big data-driven decision support system for overseas study. Through multi-source data collection, trend analysis algorithms, and personalized recommendation strategies, it constructed a comprehensive solution covering institution screening, cost calculation, application process planning, and risk assessment. System testing demonstrates that this solution offers significant advantages over traditional advisory methods in information processing and decision accuracy. It effectively addresses the diverse study abroad needs of families amid policy changes, providing a new pathway for intelligent educational decision-making.