Objective: The paper explores the inpatient services in medical institutions under the background of DRG payment reform to provide theoretical basis for the refined management of medical insurance in medical institutions. At the same time, it provides suggestions for improving the reform policy of medical insurance payment from the perspective of specialized medical institutions. Methods: Based on the DRG payment data of a tertiary specialized medical institution in Tianjin from November 2021 to September 2022, the principal component analysis method was used to conduct a statistical analysis with 12 management indicators, and the comprehensive scores of 25 clinical departments were evaluated. Results: The significance of Bartlett's Test of Sphericity was P<0.001, and the KMO statistic was 0.681, which was suitable for principal component analysis. The four principal component factors of diseases complexity, diseases types, efficiency of operation management, and quality of operation management were taken as comprehensive evaluation indicators. The departments with high comprehensive scores were mostly clinical departments with high technical value. Conclusion: The reform of medical insurance payment mode requires highly in construction and operation management ability of medical institutions. Specialized medical institutions should not only focus on the development of dominant disciplines, optimize disease management and enhance technical value, but also actively control the total medical cost, reduce the patients' burden, improve the quality of medical record and medical service satisfaction, and enhance competitive advantages. With the advancement of the reform of medical insurance payment methods, medical insurance departments and medical institutions can use data mining technology to explore the establishment of an evaluation system that matches the DRG payment model, in order to improve operational efficiency, and promote the healthy development of medical institutions.