Abstract: OBJECTIVE To evaluate the function of Shengji Yuhong Plaster treating on the wound surface necrosis secret of chronic ulcer of leg by double blind， random and contrast research. METHODS 257 chronic-ulcer-of-leg patients were divided into experimental group and control group noncentral-random-doubled. Standard clinical pathway of leg wound surface was made， and the clinical quantified integral change data of the pus rot secretion and the wound area were recorded. The data were transported to the third party data authority by clinical researcher. RESULTS Uncover the blind random grouping， the result shows the two groups were divided fairly on the parts of sex， course of disease， pathogen， location and wound area. Compare the necrotic tissue dropping off， the experimental group are much lower than the contrast group， and from the 14d till the end， the treatment effect of the experimental group could reach 1.4 times of the contrast group(P<0.01).The improvement of the experimental group's texture， color， odor， nature and amount of the wound secretion are better than the contrast group. The release of the pain of the experimental group patients are much better(P<0.01). The wound surface infection of pesudomonas aeruginosa and other unclassified bacteria of the experimental group are substantial reduced(P<0.05). Three days after treatment， the wound healing rate of the experimental group is much higher than the contrast group(P<0.01). At the end of the treatment， the average healing rate of the experimental group is around 80%， and the contrast group is about 30%. CONCLUSION Shengji Yuhong Plaster can improve the healing of the wound by the function of eliminating necrotic tissues and promoting granulation.