Abstract: Objective : To investigate the correlation of the polymorphisms in DNA repair gene XRCC1 (Arg194Trpand Arg399Gln) with clinicopathologic characteristics in Chinese women with breast cancer. Methods : Thepolymorphisms of XRCC1 were detected by PCR-restriction fragment length polymorphism assay(PCR-RFLP) in 250 primary breast cancer patients. Results : The polymorphisms of XRCC1 were not significantly associated with clinical stage, tumor size, axillary lymph node involvement, estrogen receptor status ormenopausal status (P>0.05). However, patients homozygous for the variant at XRCC1 position 194 weremore likely to have progesterone receptor (PR)-negative tumors than patients with the homozygous wild-typeor heterozygous genotype (81.0% vs. 55.4%, P=0.034). Moreover, patients homozygous for the variant at XRCC1 position 399 had a higher level of C-erbB2 overexpression in the tumors than that found in patients withthe homozygous wild-type or heterozygous genotype (61.1% vs. 29.3%, P=0.006). Conclusion : Breast cancerpatients homozygous for the variant genotype at XRCC1 position 194 or 399 may have an unfavorable clinicaloutcome.