Abstract: OBJECTIVE To explore the characteristics, distribution of pathogens and risk factors for veno-arterial extracorporeal membrane oxygenation (VA-ECMO)-associated health care-associated infections (HAIs) and observe the effect on clinical treatment outcomes. METHODS A total of 147 patients who were treated with VA-ECMO in a three-A hospital of Hubei Province from Jan. 2017 to May 2025 were retrospectively enrolled in the study and were divided into the infection group with 35 cases and the non-infection group with 112 cases according to the status of HAIs. The clinical data were compared between the two groups, univariate analysis and multivariate logistic regression analysis were performed for the related factors for HAIs, and the distribution of pathogens was analyzed. RESULTS Among the 147 patients who were treated with VA-ECMO, 35 had HAIs, with the incidence of infections 23.81%; the patients with pulmonary infections accounted for 48.57%, the patients with bloodstream infections 22.86%. Totally 59 strains of pathogens were isolated, of which 37.29% were fungi, 32.20% were gram-negative bacteria, and 30.51% were gram-positive bacteria. The result of multivariate logistic regression analysis showed that the incidence of HAIs was associated with the age, duration of invasive respiratory support, and duration of central venous catheter indwelling(P＜0.05). The total hospitalization cost of the infection group was more than that of the non-infection group, and the clinical treatment outcomes of the infection group were worse than those of the non-infection group (P＜0.05). CONCLUSIONS The incidence of HAIs is high among the patients who are treated with VA-ECMO. The fungi are dominant among the pathogens. The incidence of HAIs is associated with the old age, extended duration of invasive respiratory support and extended duration of central venous catheter indwelling. There is association between the HAIs and the poor clinical treatment outcomes. It is necessary to strengthen the early identification of the high-risk patients, prevention and control of the infections.