Objective To explore the influence of the protection motivation theory (PMT) on the self-nursing ability of high-risk diabetic foot (DF) patients. Methods The outpatients in our hospital were selected with high-risk DF between January 2013 and May 2014, randomly divided into the control group and PMT group, 52 cases in each group. Guided under the protection motivation theory, PMT group received a six-month health education and management; and the control group accepted conventional health education of diabetes. Before and after the intervention, some observation indexes of the two groups respectively were evaluated including the ability of diabetic foot self-nursing, foot condition, fasting blood sugar, 2 h postprandial blood glucose. Result After six months, the scores of the self-care ability of diabetic foot and foot condition from the patients of PMT group were higher than that of PMT group before the intervention and that of control group after intervention (P<0.05). Conclusion PMT can help patients with high-risk DF enhance their foot self-care ability, improve their foot condition, control their blood sugar, and prevent the DF onset.