Breast cancer (BC) is a cancer with a high incidence and mortality of female, threatening women's physical and mental health. Achyranthes bidentata Blume, a traditional Chinese medicine, has been popular in folk due to its effective pharmacology activities including anti-inflammatory and anti-tumour effects. In order to identify the active ingredients from the roots of A. bidentata for treating breast cancer, the separation guided by network pharmacology analysis was employed which led to the isolation of 7 triterpenoids and 10 phytosterones. According to the in vitro experiments, the isolated compounds showed significant inhibitory activities on MCF-7 cells as well as anti-inflammatory activities by attenuating the production of NO and TNF-α in LPS-induced macrophage cells. In conclusion, this study successfully predicted and confirmed the positive impact of triterpenoids and phytosterones on breast cancer, which provided a foundation for further in vivo studies.