Objective To investigate the relationship between the Clinical Frailty Scale (CFS) and prognosis in elderly patients with pelvic fractures who are treated conservatively. Methods Patients aged ≥65 years admitted to Chengdu Pidu District People’s Hospital between January 2015 and January 2023 with low-energy pelvic-ring fractures (Tile type A/B) who received non-operative management were retrospectively collected. The patients were stratified by CFS score on admission into robust (CFS 1-3), vulnerable (CFS 4), and frail (CFS 5-9) groups. Baseline characteristics (age, sex, smoking history, alcohol use, and so on) and outcomes (complications, discharge destination, and in-hospital mortality) were compared among groups. Binary logistic regression was used to assess the association between CFS and outcomes. Results A total of 197 patients were enrolled: 78 robust, 59 vulnerable, and 60 frail. Significant differences were observed among the robust, vulnerable, and frail groups in age [(68.72±2.53), (71.47±3.53), and (73.25±2.33) years, respectively; P<0.05], incidence of complications (28.2%, 33.9%, and 56.7%, respectively; P<0.05), and incidence of adverse discharge destinations (15.4%, 25.4%, and 38.3%, respectively; P<0.05). Logistic regression analysis revealed that frailty (CFS 5-9 vs. 1-3) was an independent predictor of any complications [odds ratio (OR)=3.342, 95% confidence interval (CI) (1.390, 8.037), P=0.007] and adverse discharge destination [OR=4.871, 95%CI (1.762, 13.469), P=0.002]. Conclusion CFS-assessed frailty correlates with the adverse discharge destination and any complication in elderly patients undergoing conservative treatment for pelvic fractures.