Introduction: Femoro-popliteal bypass with autologous vascular graft is a key revascularization method in chronic limb-threatening ischemia (CLTI). However, the lack of suitable autologous conduit may occur in 15–45% of the patients, necessitating the implantation of prosthetic or allogen grafts. Only little data is available on the outcome of allograft use in CLTI. Aims: Our objective were to evaluate the long term results of infrainguinal allograft bypass surgery in patients with chronic limb-threatening ischemia (CLTI) and compare the results of arterial and venous allografts. Methods: Single center, retrospective study analysing the outcomes of infrainguinal allograft bypass surgery in patients with CLTI between January 2007 and December 2017. Results: During a 11-year period, 134 infrainguinal allograft bypasses were performed for CLTI [91 males (67.9%)]. Great saphenous vein (GSV) was implanted in 100 cases, superficial femoral artery (SFA) was implanted in 34 cases. Early postoperative complications appeared in 16.4% of cases and perioperative mortality (<30 days) was 1.4%. Primary patency at one, three and five years was 59%, 44% and 41%, respectively, while secondary patency was 60%, 45% and 41%, respectively. Primary patency of the SFA allografts was significantly higher than GSV allografts (1 year: SFA: 84% vs. GSV: 51% p = 0,001; 3 years: SFA: 76% vs. GSV: 32% p = 0,001; 5 years: SFA: 71% vs. GSV: 30% p = 0.001). Both primary and secondary patency of SFA allograft implanted in below-knee position were significantly higher than GSV bypasses (p = 0.0006; p = 0.0005, respectively). Limb salvage at one, three and five years following surgery was 74%, 64% and 62%, respectively. Long-term survival was 53% at 5 years. Conclusion: Allograft implantation is a suitable method for limb salvage in CLTI. The patency of arterial allograft is better than venous allograft patency, especially in below-knee position during infrainguinal allograft bypass surgery. [ABSTRACT FROM AUTHOR]