© 2021 The Author(s).Introduction: Lower-extremity peripheral artery disease (PAD) can lead to a wide spectrum of symptoms that can progress from claudication to amputation. The prognostic nutritional index (PNI), which is calculated using the levels of albumin and lymphocyte, is an accepted indicator of immunological and nutritional status. In this study, the association between nutritional status determined using the PNI, and extremity amputation in patients with lower-extremity PAD was investigated. Methods: Lower-extremity PAD patients who had been admitted to the cardiology clinic of the Dişkapi Yildirim Beyazit Training & Research Hospital with stage 2b or higher claudication, and who were technically unsuitable for revascularization or underwent unsuccessful revascularization procedure were enrolled in this retrospective study. Patients were grouped according to whether or not limb amputation had been performed previously. Potential factors were tested to detect independent predictors for amputation with logistic regression analysis. Results: A study group was formed with 266 peripheral artery patients. The amputated group (39 patients) had a higher number of hypertensive (76.9% vs 57.7%; P = 0.032) and diabetic (92.3% vs 54.2%; P < 0.001) patients than those in the non-amputated group (227 patients). The median PNI value of the amputated group was lower than that of the non-amputated group (31.8 vs 39.4; P < 0.001). Multivariate logistic regression showed that the PNI (OR: 0.905, 95% CI: 0.859 - 0.954; P < 0.001) was independently related with amputation. Conclusion: Immune-nutritional status based on PNI was independently associated with limb amputation in patients with lower-extremity PAD.