Diabetes mellitus is a worldwide problem on the rise, affecting almost half a million people around the globe, with countless impacts on the health and quality of life of this population. The objective was to determinate the prevalence and risk factors associated with amputation due to Diabetes mellitus, focusing on those related to primary care, self-care and socioeconomic profile. This study was cross-sectional, quantitative and descriptive. Data were collected from questionnaires applied to patients over 18 years old with lower limb amputations, attended at the Integrated Clinics of a University in the south Brazil. The results showed a prevalence of 85.70% of amputation by diabetes. The sample was predominantly composed of men, elderly, retired, married, with low schooling and low socioeconomic status. Most of the diagnosis of diabetes mellitus between the period of five to ten years, 88.9% used oral antidiabetics and 63.9% used insulin. The ulcer prior to amputation was present in 80.6% of the patients. Of the sample, 55.6% reported having their feet evaluated by a health professional, while 38.9% of them reported annual or rarely evaluation frequency. In addition, questions related to self-care also demonstrated a great lag, especially with regard to blood glucose measurement, foot self-examination and shoe evaluation. Consequently, educational actions of care, including the evaluation of the feet, should be promoted to health professionals and prioritized in people with diabetes, aiming at the prevention of the innumerable complications of this comorbidity, mainly the amputation by diabetic foot.