Abstract: The purpose of this study is to investigate the effect of platelet-derived extracellular vesicles (EV) on proliferation and invasion of breast cancer cells. The study found that EVs were internalized by MDA-MB-231, T47D, and 1590 cells in a time-dependent manner. The EVs in these cells remained at a high presentation level, and showed a trend of gradual increase. EV could increase the number of breast cancer MDA-MB-231 cells passing through the compartment membrane, reduce the concentration of Ca 2+, and increase the expression levels of p38, MAPK, Akt, and p-Akt. Obviously, EV had a pro-invasive effect on breast cancer MDA-MB-231 cells, which may be underlain by its mediation of TRPC5 signaling pathway and inhibition of Ca 2+ efflux. This study provides a more reliable approach for assessing the progression and prognosis of breast cancer.