This study was to investigate the efficacy and safety of Nocardia rubra Cell Wall Skeleton (NCWS) in the treatment of diabetic foot ulcer wounds. The study was a prospective, randomized, controlled, multicentre study . The subjects were randomly divided into two groups: NCWS group and control group（silver ions dressing）, with a total of 116 cases and 58 cases in each group. Patients in the NCWS group received nocardia rubra cell wall skeleton for external use, in parallel with silver ions dressing treatment. The efficacy and side effects were observed, with a primary endpoint of 30-days wound healing rate.

Inclusion Criteria:

• ages 18 to 80 years old (including 18 and 80 years of age), gender not limited;
• in patients with type 2 diabetic foot, in 1999 the WHO diagnostic criteria, diabetic foot screening period or three months before randomization glycated hemoglobin (HbA1C) was detected in 10% or less;
• the target body ankle brachial index of at least 0.8, without intermittent claudication walkers;
• the target ulcer must have the following characteristics: A) according to the Wagner ulcer classification system for level 1 or level 2 B) ulcer is located in the foot, ankle and shin before; C) wound area of 2-5 cm2; D) has existed at least 4 weeks before randomization; E) if you have multiple wounds, select into the set standard and area is one of the biggest intervention and evaluation of the wound.The rest of the wound conventional treatment is not included in the study;If there are two or more wounds are the biggest, choose the worst into classification research;If there are two or more wound area and the classification, choice wound area are the longest study; F) without visible pus and necrotic material;
• voluntary to participate in this clinical study, cooperate a doctor to conduct research, and sign the informed consent.

Exclusion Criteria:

• with clear surgical indications, such as vascular occlusion, bone exposed, abscess, osteomyelitis, etc;
• into the group of the first 3 months of vascular reconstruction or angioplasty;
• impaired liver function (ALT and AST 3 times more than normal limit, AST, aspartate amino transferase;ALT: alanine aminotransferase);
• serum creatinine greater than 2 times the upper limit of normal value;
• serum albumin < 2.0 g/dL;
• is undergoing immunosuppressive medication;
• Various malignant tumor patients ;
• of pregnant women, nursing mothers, or in the near future with family planning; ● with nerve, mental disorders and can't cooperation or unwilling to partners, has a history of alcoholism, drug abuse, and failed to quit;
• into the group of the first 3 months participated in other clinical subjects; Cartesian bacteria cell wall
• to use red, skeleton or silver products are taboo, allergies or known allergies;
• researchers believe that patients should not participate in this study to other situations.