Objective: The paper analyzes the implementation and effectiveness of DIP-based disease cost management in a first-class hospital in Shenzhen, and summarizes the practical experience in cost management. Methods: A total of 21507 patients included in 5249 disease groups in radiotherapy and oncology departments from 2021 to the first quarter of 2023 was collected, and time series analysis was used to make the descriptive and statistical analysis of DIP cost data. Results: By the first quarter of 2023, the difference between the average DIP revenue and the average project revenue, and the average DIP income and expenditure balance of the two representative departments all turned from deficit to surplus. The total per capita hospitalization cost, medical service cost, examination cost and laboratory cost have positive feedback (P < 0.05), and the cost was to some extent managed. The profit and deficit of the disease groups with diagnosis of C34.0, C54.1, C78.2, Z08.0 and Z51.1 were correlated with the implementation of DIP cost management, and the profit rate of each disease group increased. Conclusion: The implementation of DIP-based disease cost management can improve the accuracy of disease enrollment, achieve higher average DIP income than the project income of diseases and the average DIP income and expenditure surplus, and effectively manage medical expenses and improve the surplus rate of diseases. This study can be a reference for understanding and promoting the practice of DIP-based disease cost management in China.