Objective To understand the economic losses due to healthcare-associated infection (HAI) in patients after Da Vinci robotic thoracic surgery, and provide basis for preventing and controlling HAI after robotic surgery. Methods Patients who underwent Da Vinci robotic surgery from April 2019 to April 2023 were retrospective stu-died. Patients were divided into HAI group and non-HAI group based on the occurrence of postoperative infection. Through 1 ∶1 propensity score matching (PSM), 31 cases were included in each group, economic losses of two groups of patients were compared. Results A total of 921 patients who underwent Da Vinci robotic thoracic surgery were included in the study, 51 cases with HAI (HAI group) and 870 without HAI (non-HAI group). After 1 ∶1 PSM, 31 cases were included in each group. Four covariates were compared between two groups of patients before PSM, namely gender, age, comorbidities, and the American Society of Anesthesiologists (ASA) grading, all with statistically significant differences (all P<0.05). After PSM, distribution of the above covariates reached equilib-rium between the two groups (both P>0.05). The median total expense for HAI group before PSM during hospitalization was 88 711.72 Yuan, while 78 509.46 Yuan for the non-HAI group. The direct economic losses caused by HAI after Da Vinci robot surgery was 10 202.26 Yuan, mainly increased by expense of medicine, nursing, laboratory diagnosis, etc. Difference in western medicine expense was the highest (8 839.12 Yuan), out of which expense of antimicrobial agents accounted for the highest proportion ( 73.55%). Difference in daily hospitalization expense between HAI-group and non-HAI group was 502.38 Yuan. Length of hospital stay of patients in HAI group and non-HAI group were (21.59±10.62) and (13.92±9.21) days, respectively, with statistical differences (all P<0.05). Conclusion The occurrence of HAI in patients undergoing Da Vinci robotic thoracic surgery leads to direct economic losses, with obvious increases in expenses of nursing, laboratory diagnosis, western medicine (mainly antimicrobial agents). Length of hospital stay of patients also prolongs.