Objective To compare the expression of drug resistance gene mdr1 between keloid fibroblast（KF） and normal dermal fibroblast（NF）. Methods The expression of drug resistance gene mdr1 and its corresponding protein ABCB1 in KF and NF were assessed with real-time PCR, immunohistochemical and flow cytometry. The expression of ABCB1 protein in 30 cases of keloid was analyzed by flow cytometry. Results The expression of mdr1 and ABCB1 in keloid was significantly higher than in normal skin; The expression rate of ABCB1 of the primary fibroblasts in pectoral keloid was higher than in abdominal and dorsal keloid. Conclusion Drug resistance gene mdr1 and its corresponding protein ABCB1 are all expressed in KF, and the expression amount is much higher than in NF.