Background and purpose: Postoperative fatigue (POF) is a common and distressing post-operative symptom. This study aimed to explore the relationship between neutrophil-to-lymphocyte ratio (NLR) and POF in elderly patients with hip fracture.Method: Elderly patients (age ≥ 65 years) with acute hip fracture admitted to the Department of Orthopedics of Anqing Hospital affiliated to Anhui Medical University from June 2018 to June 2020 were included. Fatigue was assessed using the Fatigue Severity Scale at the 3-month follow-up postoperatively. Univariate and multivariate analyses were performed to explore the associations between NLR and POF. The diagnostic performance of NLR was analysed using Receiver Operating Characteristic (ROC) curve analysis and the Delong test.Result: A total of 321 elderly patients with hip fractures were included; 120 (37.4%) of them were diagnosed with POF. Univariate analysis indicated significant differences in NLR, platelet-to-lymphocyte ratio (PLR), education, neutrophil count, lymphocyte count, Hamilton Depression Scale (HAMD) and Insomnia Severity Index (ISI) scores (P<0.05). Multivariate analysis indicated neutrophil count (odds ratio [OR], 1.46; 95% confidence interval [CI] 1.27–1.67), lymphocyte count (OR 0.32, 95% CI 0.19–0.53), NLR (OR1.81, 95% CI 1.50–2.17) and PLR (OR 1.005, 95% CI 1.001–1.009) were significantly associated with POF. The areas under the ROC curves (AUCs) of neutrophil count, lymphocyte count, NLR and PLR were 0.712, 0.667, 0.775 and 0.605, respectively. The Delong test indicated that NLR had the best diagnostic performance (p < 0.05).Conclusion: NLR independently predicts POF in elderly patients with acute hip fracture.