Abstract: OBJECTIVE Based on Diagnosis Related Groups (DRG), to analyze the direct economic burden caused by infections in orthopedic specialty hospitals. METHODSA retrospective analysis was conducted on the basic information of infection cases in Ningbo No.6 Hospital from 2022 to 2023, and all discharged cases in the same DRG groups were matched. The average length of stay and average hospitalization expenses were compared between patients with and without hospital-associated infections in terms of overall, different infection sites and different DRG groups. RESULTSAmong the inpatients managed under DRG, hospital-associated infections occurred in 77 DRG subgroups, with 660 cases of hospital-associated infections and 63 948 cases without hospital-associated infections. The average length of stay and average hospitalization expenses of patients with hospital-associated infections were higher than those without hospital-associated infections (P<0.05). The most noteworthy DRG subgroup was IS13Z, where hospital-associated infections resulted in an increase in hospitalization expenses (71 000 yuan) and an extended length of stay (30.96 days). The extended length of stay due to infections in patients in the BS03B group reached 32.31 days, and the increase in hospitalization expenses due to infections in patients in the IS04B group reached 94 600 yuan. The sites of hospital-associated infections included skin and soft tissues, surgical sites, urinary system, respiratory system, blood system and craniocerebral system, accounting for 55.91%, 22.27%, 10.00%, 7.73%, 3.03% and 1.06%, respectively. The average length of stay/hospitalization expenses of patients with hospital-associated infections at different infection sites were higher than those of patients without hospital-associated infections in the same DRG group (P<0.05). In the surgical site infection group, there was no difference between the group diagnosed with hospital-associated infection during the first hospitalization and the group diagnosed with hospital-associated infection upon readmission. CONCLUSIONThe evaluation of the economic burden caused by infections in orthopedic specialty hospitals based on DRG can accurately quantify infection control risks, optimize prevention and control measures, reduce infection rates and medical expenses, improve operational efficiency, and provide data support for DRG policy adjustments.