AIM: To investigate the effect of 3-methyladenine (3-MA) combined with trichostatin A (TSA) on triple-negative breast cancer cells and the mechanism involved.METHODS: The viability of MDA-MB-231 cells was detected by MTT assay, the migration ability was determined by scratch assay, and the expression of autophagy-related proteins was detected by Western blot.RESULTS: TSA significantly inhibited the viability of MDA-MB-231 cells in a time-and dose-dependent manner.The results of scratch assay showed that TSA inhibited cell migration ability.Western blot data indicated that TSA resulted in a moderate increase in LC3-Ⅱ expression.Moreover, 3-MA inhibited cell autophagy induced by TSA, and combination of 3-MA and TSA further inhibited the viability of MDA-MB-231 cells.CONCLUSION: Combination of 3-MA and TSA may effectively inhibit the growth of triple-negative breast cancer cells.