To observe clinical effect of earthworm extract in treating diabetic foot.Methods：Ninety two patients meeting the conclusion criteria were divided into treatment group (n=40) and control group (n=52) according to a random number table. Two groups both applied conventional western medicine, while treatment group gave patients extra application of earthworm extracts. Wound healing condition, clinical symptoms improvement, serum c-reactive protein (CRP), insulin growth factor (IGF-1), vascular endothelial growth factor (VEGF), and adverse events were observed.Results：The total effective rates of the treatment group and the control group were respectively 90% and 82.69%, which showed a statistically significant difference (P<0.05).The changes of the ulcer area, purulent secretions, and granulation tissue before and after treatment in both groups showed statistically significant differences (P<0.05).The time of wound healing in treatment group was faster than that of the control group, which showed a statistically significant difference (P<0.05). After treatment, CRP of patients in the treatment group were lower than that of the control group, and IGF-1 was higher in the treatment group, showing statistically significant differences between the groups (P<0.05). From the seventh day of the treatment, serum VEGF of the patients in treatment group was higher than that of the control group, and there were statistically significant differences between the two groups in different time (P<0.05). There were no adverse reactions occurred in both groups.Conclusion：Earthworm extracts combined with routine western medicine treating diabetic foot shows safe and reliable therapeutic effects, and it is better than the single usage of western medicine in terms of improving the ulcer area, purulent secretions, and granulation tissue, accelerating wound healing. Its mechanism may be related to lowering CRP, upgrading the level of IGF-1 and VEGF.