Aim To investigate the causes, risk factors, severity of diabetic foot and prognostic factors of amputation. Methods 284 inpatients with diabetic foot who met the inclusion criteria were enrolled in the Endocrinology Department, from January, 2006 to December, 2010. Their clinical data were collected for retrospective study. Binary Logistic regression analysis was used to identify risk factors for the severe diabetic foot and amputation. Results Of these 284 patients, 175 were men and 109 were women. 82.4% of patients were older than 50. The diabetes duration in 77.5% patients was more than 5 years. Glycosylated hemoglobin （HbA1c） in 86.5% patients was higher than 6.5%. Diabetic foot ulcers mostly occured in the toe. The main causes of diabetic foot were burn or scald. The positive rate of bacterial culture in diabetic foot ulcer secretions was 94.8%, and diabetic foot was often accompanied with diabetic nephropathy and diabetic retinopathy. Serum albumin （ALB）, total cholesterol （TC）, high density lipoprotein cholesterol （HDLC）, red blood cell count and hemoglobin （Hb） in patients with Wagner 3～5 （Severe group） were lower than that in patients with Wagner 0～2 （Mild group） （P<0.05）, and white blood cell count and platelet count in severe group were higher than that in mild group （P<0.05）. Severe patients were predisposed to diabetic ketoacidosis, diabetic