Objectives : The aim of this study was to find the desirable way for the acupuncture treatment of breast cancer. Methods : We reviewed several literatures about breast cancer. Based on the review, we analyzed the causes of breast cancer through meridian theory of oriental medicine and looked for the desirable ways to treat it. Results and Conclusions : The breast cancer results from the unbalance between reverting yin and lesser yang. Especially, exasperation of PC(pericardium meridian) seems to paly an important role, and accordingly, it is needed to activate GB(gall bladder meridian). Also, enhancing the function of HT(heart meridian) should be considered for the acupuncture treatment of breast cancer.