ZHU Danxi focused more on the protection of yin-blood in terms of clinical treatment believing that yinessence was difficult to be formed and easy to be lost，and proposed the famous theory of"yang being often in excess while yin being often in deficiency".Starting from this theory of ZHU Danxi，this paper discusses its guiding role in postoperative chemoradiotherapy of breast cancer treated by Chinese medicine，and puts forward that we should pay attention to nourishing yin in the syndrome differentiation and treatment of this disease，which can provide ideas for the treatment of breast cancer by Chinese medicine.