Objective To study the economic losses of hospitalized patients and hospitals due to healthcare-associated infection (HAI) under the diagnosis intervention packet (DIP) medical insurance payment mode, and provide support from the perspectives of warning for high-risk infection in patients, hospital cost operation, and reverse control by medical insurance departments. Methods The length of hospital stay and hospitalization expenses of HAI patients in mixed group (including cases of self-payment, medical insurance payment [8 DIPs and those without included in DIPs]) in a hospital from 2022 to 2023 was analyzed retrospectively, and compared with non-HAI patients with the same type of disease during the same period. Length of hospital stay and hospitalization expenses due to HAI in patients with DIP payment, as well as direct economic losses of hospital resulting from HAI after DIP settlement but before medical insurance sharing expense were analyzed using the same method, and compared with non-HAI patients of the same DIP disease during the same period. Results From 2022 to 2023, the average length of hospital stay and hospitalization expenses due to HAI in patients in the mixed group and those with DIP payment were higher than non-HAI patients with the same types of disease during the same period, differences were all statistically significant (all P<0.05). In 2022-2023, the direct economic losses of hospital after DIP settlement but before medical insurance shared expense for HAI patients were higher than those of non-HAI patients with the same DIP disease type during the same period, differences were both statistically significant (both P<0.05). According to the analysis of different HAI sites, the highest hospitalization expense for patients in 2022 and 2023 were due to bloodstream infection (39 644.03 Yuan and 33 289.34 Yuan, respectively). The HAI sites with the highest direct economic losses in 2022 and 2023 were lower respiratory tract (6 617.25 Yuan) and surgical sites (9 853.40 Yuan). The infection site with the highest actual economic losses caused by HAI in 2022 and 2023 was surgical site (9 831.30 and 13 132.54 Yuan, respectively). Conclusion HAI significantly increases the economic losses of hospitalized patients, but the DIP medical insurance payment model can limit the length of hospital stay and hospitalization expenses of HAI patients. The highest economic losses for hospitalized patients and hospitals vary in different infection sites. It is necessary to comprehensively judge and determine the priority of projects for risk prevention and control in hospital, develop a high-risk infection patient model for the project to reduce HAI risk, and assist the medical insurance department in reducing hospital economic losses.