Objective：This stndy aims to investigate the application prospect of lawsone in the treatment of triple negative breast cancer（TNBC）. Methods：Two TNBC cell lines，MDA-MB-231 and SUM1315，were selected as the research subjects. The effects of lawsone on breast cancer cells were investigated by CCK-8 assay，wound-healing assay，cellular invasion assay，colony formation assay，EdU assay and cell cycle assay. Results：The 72-hour IC50 values of MDA-MB-231 and SUM1315 were 249.87 μmol/L and 158.34 μmol/L，respectively. Lawsone could significantly inhibit the migration，invasion and proliferation of breast cancer cells，and prolong the G1 phase of breast cancer cell cycle. Conclusion：Lawsone may affect the occurrence and development of breast cancer by inhibiting the migration，invasion and proliferation of breast cancer cells.