Diabetic foot infection (DFI) is a common problem in patients with diabetic foot disease. Amputations and other complications of DFI lead to significant morbidity and mortality. The Society for Vascular Surgery (SVS)-WIfI (wound, ischemia, and foot infection) classification system can evaluate the benefit from revascularization and the risk of amputation in 1 and 3 years. We aimed to evaluate SVS-WIfI and Wagner-Meggitt (WM) prediction of DFI outcome, and to determine factors associated with major amputation and mortality rate. The patients with diabetes who presented between June 2018 and May 2020 with characteristics suggesting a more serious DFI or potential indications for hospitalization were reviewed in this cohort study. Demographic data, clinical characteristics, and type of revascularization were evaluated. One-year and 3-year amputation and mortality rates were the main outcomes. The grading of WM classification and the SVS-WIfI score were compared between amputation and nonamputation groups. Association between mortality and comorbidity were analyzed. One hundred and thirty-one patients admitted with DFI were included in study. And 73.28% had peripheral arterial disease (PAD). The 1-year and 3-year major amputation rates were 16.03% and 26.23%, respectively. Seventy-eight (59.54%) patients required minor amputation to control infection before revascularization. PAD (risk ratio [RR] 1.47: 95% confidence interval [CI] 1.29-1.67, P = .032), benefit from revascularization clinical stage 3 on SVS-WIfI score (RR 4.56: 95%CI 1.21-17.21, P = 0.007), and high WM classification score (RR 9.46: 95% CI 5.65-15.82, P < 0.001) were associated by multivariate analysis with high amputation rates. 1-year & 3-year amputation risk on SVS-WIfI score were not associated with amputation rates in DFI (P = .263 and .496). Only 9 (6.8%) patients were lost to follow up during the 3-year period. WM classification score, SVS-WIfI score on benefit from revascularization, and PAD were strongly associated with major amputation rates in patients with DFI.