Abstract: Objective To investigate the association between the CYP1B1 gene rs1056836 polymorphism and the susceptibility to breast cancer in Xinjiang Uygur women. Methods Polymerase chain reaction restriction fragment length polymorphism（PCR-RFLP） was performed to detect the polymorphism of the CYP1B1 gene rs1056836 between 125 cases of Uygur women with breast cancer and 160 cases of healthy Uygur women and the relationship between polymorphic loci and the susceptibility to breast cancer was analyzed. Results CYP1B1 gene in the rs1056836 site had three genotypes， namely CC，CG，GG. The distribution frequency of three genotypes were 43.2％，51.2％，5.6％ in the breast cancer group， and were 60.6％， 34.4％， 5.0 ％ in the healthy control group. There was significant differences for distribution of three genotypes between two groups （P＜005）. The distribution frequency of allele C，G was 68.8％，31.2％ in the breast cancer group and 77.8％，22.2％ in the healthy control group with statistical difference significantly （P＜0.05）. Logistic regression univariate analysis showed that carrying the CC genotype reduces the risk of breast cancer in Uygur women. Stratification analysis of risk factors of breast cancer suggested that compared with wild genotype CC，carrying CG， GG genotype in the early menarche，family history of cancer and premenopausal Xinjiang Uygur women increased risks of breast cancer. Conclusion The polymorphism of CYP1B1 rs1056836 is significantly associated with the susceptibility to breast cancer in Uygur women. CYP1B1 rs1056836 mutation genotype increases the risk of breast cancer in Xinjiang Uygur women.