Objective To observe the clinical efficacy and discuss the mechanism of Quyu Jiedu Formula（ Formula for removing stasis and toxins） in the treatment of endometriosis（ EM）. Methods Totally 60 EM patients with blood stasis and toxin accumulation syndrome were randomly divided into treatment group and control group

with 30 cases each. The treatment group was given Quyu Jiedu Formula in herbal paste

while the control group was given Dan’ e Fukang Decocted Extract. The treatments started after the end of menstrual period and lasted for 20 days.Treatment course was 3 menstrual periods. The symptom scores

dysmenorrhea scores were recorded and the expression of interleukin-6（ IL-6）

soluble intercellular adhesion molecule-1（ s ICAM-1） and eutopic endometrim cells’ intercellular adhesion molecule-1（ ICAM-1） was detected before and after treatments

so as to determine the clinical efficacy. Results The overall effective rate was 83. 33% in the treatment group and 60. 00% in the control group

the results in the treatment group was superior（ P < 0. 05）. The symptom scores

dysmenorrhea scores were significantly lower after treatments and the expression of IL-6

s ICAM-1 in serum was reduced and eutopic endometrim cells’ ICAM-1 was increased with statistical significance（ P < 0. 05）. Also all indexes from above in the treatment group were improved in a larger scale than in the control group（ P < 0. 05）. Conclusion Quyu Jiedu Formula was effective in EM patients with blood stasis and toxin accumulation syndrome. The mechanism could be the down-regulated expression of serum IL-6 and s ICAM-1

as well as up-regulated expression of eutopic endometrim cells’ ICAM-1.