Abstract:Objective：To analyze the impact of the DRG payment reform on the hospitalization costs and cost structure changes of patients undergoing surgery for thyroid malignant tumors，providing a reference for refined hospital management. Methods：Propensity Score Matching（PSM）was utilized to eliminate potential differences before and after the implementation of DRG. Grey relational analysis and structural change analysis were employed to compare the hospitalization costs and cost structures of patients with thyroid malignant tumors who underwent surgery in a tertiary hospital in Anhui Province from 2019-2020（before DRG reform）and 2021-2022（after DRG reform）. Results：After the implementation of DRG，the average hospitalization cost per patient decreased significantly from 16 966.05 RMB to 15 780.88 RMB（P < 0.001）. Except for surgical costs，all other costs and the length of hospital stays were reduced，with statistical significance（P < 0.05）. The gray relational analysis indicated that drug costs and diagnostic fees had the highest correlation with hospitalization costs. Structural change analysis revealed that drug costs（30.37%）and medical surgical fees（44.57%）were the main factors causing changes in the cost structure. Conclusion：The DRG payment reform has effectively reduced the hospitalization costs for patients undergoing surgery for thyroid malignant tumors and optimized the cost structure，which is of significant guiding importance for hospital management.