Objective: The anesthesia residency training system is designed to provide supervised practice, enabling residents to progress from simple to complex procedures and higher-risk patients. However, it remains unclear whether residents acquire sufficient competence to be considered qualified anesthesiologists by the end of their training. This study aimed to evaluate whether anesthesia care provided by supervised CA-5 residents affects postoperative outcomes in elderly patients undergoing non-cardiac surgery. Methods: A retrospective analysis was conducted on clinical data from elderly patients who underwent non-cardiac surgery between January 2020 and December 2021 at Songjiang Hospital Affiliated to Shanghai Jiao Tong University School of Medicine. Patients were categorized into two groups: those managed by CA-5 residents (Resident group, n=294) and those managed by attending anesthesiologists (Attending group, n=521). Propensity score matching (PSM; 1:1) was used to ensure comparability between the groups. The primary outcome was a composite of in-hospital postoperative complications. Secondary outcomes included intraoperative hemodynamic changes, the need for intensive care unit (ICU) admission, length of ICU and hospital stays, and in-hospital mortality. Multivariable logistic regression assessed the adjusted association between anesthesia provider type and postoperative morbidity and mortality. Results: Among the 815 elderly patients included, 105 (12.9%) experienced postoperative complications and 22 (2.7%) died during hospitalization. No significant differences were observed in postoperative complications or mortality between the two groups, either before PSM (morbidity: 11.9% vs. 13.4%, p=0.531; mortality: 3.7% vs. 2.1%, p=0.168) or after PSM (morbidity: 12.0% vs. 14.4%, p=0.392; mortality: 3.8% vs. 1.4%, p=0.067). Multivariate analysis confirmed that postoperative morbidity and mortality were not significantly associated with resident involvement, either before PSM (morbidity: OR=0.882, 95% CI: 0.552-1.410, p=0.600; mortality: OR=1.293, 95% CI: 0.479-3.492, p=0.612) or after PSM (morbidity: OR=0.881, 95% CI: 0.523-1.486, p=0.636; mortality: OR=3.122, 95% CI: 0.805-12.106, p=0.100). Conclusions: Postoperative morbidity and mortality rates in elderly patients undergoing non-cardiac surgery are comparable between those anesthetized by supervised CA-5 residents and those managed by attending anesthesiologists. These results suggest that supervised CA-5 residents do not adversely affect patient safety.