Objective To evaluate the associations between carbapenem-resistant Acinetobacter baumannii (CRAb) detected from any respiratory specimens within 0-7 days after lung transplantation and all-cause mortality at 30-day, 90-day and 1-year post-transplantation. Methods Recipients undergoing lung transplantation at Lung Transplant Center of Wuxi People’s Hospital Affiliated to Nanjing Medical University from January 1, 2020 to December 31, 2022 were retrospectively enrolled. Patients were divided into the CRAb-positive group (n=126) and CRAb-negative group (n=299) according to culture results of respiratory samples collected within postoperative days 0-7. Baseline characteristics were compared between the two groups. Univariate and multivariate Cox regression models were performed to identify risk factors for 30-day mortality and analyse the correlation of CRAb detection with 30-day, 90-day and 1-year all-cause mortality. Sensitivity analyses and subgroup analyses were subsequently conducted. Results Compared with the CRAb-negative group, recipients in the CRAb-positive group presented higher ratios of preoperative invasive mechanical ventilation and extracorporeal membrane oxygenation (ECMO), a higher CRAb-positive rate in donor pharyngeal swabs, and elevated proportions of bilateral lung transplantation, Shell-shaped incision, peri-operative ECMO application. Moreover, the CRAb-positive group had longer pulmonary cold-ischemia time, intensive care unit stay duration and operation time (all P<0.05). Multivariate Cox regression demonstrated that positive CRAb isolation from respiratory samples within postoperative days 0-7 and preoperative coronary stent implantation were independently associated with 30-day mortality (all P<0.001). The CRAb-positive group exhibited significantly higher mortality risks at 30 days, 90 days and 1 year after surgery (all P<0.001). After adjusting for confounders, early CRAb detection remained an independent predictor of elevated mortality (all P<0.05). Consistent results were obtained when stratifying cases by detection timing (0-3 days vs. 4-7 days), excluding patients with co-detection of other multidrug-resistant bacteria, and applying inverse probability of treatment weighting, and the direction of association remained consistent. Conclusions CRAb detected from respiratory specimens within postoperative days 0-7 is independently correlated with increased 30-day, 90-day and 1-year all-cause mortality among lung-transplant recipients. Early CRAb detection may serve for risk stratification. Nevertheless, such finding does not confirm that CRAb infection directly causes death, and the conclusion cannot be generalized to deaths occurring within the initial postoperative 7-day period.