Objective: The paper analyzes the effectiveness and governance transformation characteristics of medical insurance fund supervision during the 14th Five-Year Plan period, to provide references for improving the supervision system during the 15th Five-Year Plan period. Methods: Based on data from the National Healthcare Security Administration's Statistical Communiqués on the Development of Healthcare Security Undertakings (2021-2025), descriptive statistics and trend analysis were employed to examine five dimensions: recovery scale, recovery structure, intelligent supervision, criminal enforcement, and institutional innovation. Results: During the 14th Five-Year Plan period, the scale of recovered medical insurance funds expanded year by year, with an annual trajectory characterized by "low in the early years and high in the later years". Agreement management served as the primary channel for fund recovery, accounting for nearly 80%. Intelligent supervision extended the regulatory frontier to pre-event and in-event stages, with the effectiveness of pre-event reminders and in-event payment refusals gradually becoming evident. In 2025, the medical insurance payment qualification management system was fully implemented, extending supervision from institutions to individuals. Conclusion: During the 14th Five-Year Plan period, medical insurance fund supervision exhibited a transformation trend from post-investigation to whole-chain prevention and control, from institutional supervision to the dual constraint of "institutions plus individuals", and from manual inspection to a combination of intelligent screening and targeted enforcement. A multi-level supervision system has largely taken shape. Nevertheless, problems persist—insufficient clinical-dimension coverage of intelligent supervision rules, difficulties in identifying emerging violations under payment method reform, and inadequate grassroots supervision capacity. During the 15th Five-Year Plan period, further efforts are needed to refine the rule system, strengthen coordination between payment and supervision, and enhance capacity building.