Abstract: OBJECTIVE To observe the influence of degree of lower extremity vascular lesions on spectrum of pathogens causing bacterial infections in patients with diabetic foot and their drug resistance so as to provide guidance for control of the diabetic foot infections. METHODS A total of 139 diabetic foot patients complicated with bacterial infections who were treated in the hospital from Jan 2016 to Dec 2016 were enrolled in the study and divided into the grade A group with 32 cases, the grade B group with 37 cases, the grade C group with 40 cases and the grade D group with 30 cases according to the degree of lower extremity vascular lesions.The etiological test was carried out for ulcer secretions that were obtained from the 4 groups of patients, the drug susceptibility testing was performed, and the correlation between the degree of lower extremity vascular lesions and the infections was observed. RESULTS The proportion of the patients with deep infections was increased with the aggravation of lower extremity vascular lesions, and there was significant difference (P＜0.01).Totally 185 strains of pathogens were isolated from the 139 patients, of which 40.54% were gram-positive bacteria, 56.22% were gram-negative bacteria, and 3.24% were fungi.The gram-negative bacteria accounted for 69.64% in the grade C group, 72.73% in the grade D group, significantly higher than 33.33% in the grade A group and 43.48% in the grade B group(P＜0.05).Of the 139 patients, 61.15% had single infection, and 38.85% had mixed infections; the proportion of the patients with mixed infections was increased with the aggravation of lower extremity vasscular lesions, and there was significant difference (P＜0.01).The drug resistance rates of the gram-positive bacteria to cefazolin, ampicillin and oxacillin were as high as 100.00%, however, the drug resistance rates to vancomycin and linezolid were 0.The drug resistance rates of the gram-negative bacteria to ampicillin, piperacillin and ceftriaxone sodium were as high as 100.00%, and the drug resistance rates to meropenem and imipenem were 0.The proportion of the isolated multidrug-resistant strains was 17.95% in the grade A group, 26.09% in the grade B group, 33.93% in the grade C group, 36.36% in the grade D group, and there was no significant difference. CONCLUSION The proportions of the patients with deep infections, the patients with mixed infections and the isolated multidrug-resistant strains are increased with the aggravation of the lower extremity vascular lesions.It is necessary for the hospital to strengthen the monitoring of the infections in the diabetic foot patients complicated with lower extremity vascular lesions so as to reduce the rate of amputation.