Objective: To evaluate clinical effect of adipose-derived stem cells (ADSCs) local injection in treatment of chronic wound in diabetes mellitus patients. Methods: A total of 100 diabetic patients with chronic ulcer difficult healing wounds were enrolled and divided randomly into a control and an observation groups (50 cases for each). The control group received routine comprehensive therapy including surgical debridement, sterile gauze covering and closed negative pressure drainage, and the observation group adopted ADSCs local injection for continuous 4 weeks. Wound healing rate and infection rate, pain Visual Analogue Score (VAS) and wound quantitative integral were compared after 1, 2 and 4 weeks. Vascular endothelial growth factor (VEGF) expression and microvessel density in wound margin tissues were detected. Results: The wound healing rate in the observation group was significantly higher than that in the control group, and the bacterial infection rate was lower, there were statistically significant differences (P<0.05). What’s more, the pain VAS score and wound quantitative integral after 1, 2 and 4 weeks in observation group were more less (P<0.05). Furtherly, the wound VEGF level and microvessel density in observation group were higher, there was statistically significant difference (P<0.05). Conclusion: ADSCs local injection can improve wound healing rate, reduce bacterial infection, alleviate pain, increase wound VEGF expression and microvessel density formation in diabetic patients with chronic wounds, which is better safety and effectiveness.