The aim of this study was to investigate the effects of extracellular vesicles (EVs) on the proliferation and steroid hormone synthesis of bovine ovarian cortical stromal cells in vitro. The release and uptake of EVs are the new mechanisms of cell-to-cell communication. Using reverse transcriptase polymerase chain reaction, enzyme-linked immunosorbent assay, TUNEL and other experiments, we found that EVs in bovine follicular fluid can promote the proliferation and synthesis of androstenedione and progesterone in ovarian cortical stromal cells. Moreover, 100μg/ml EVs caused the most significant effect. We conclude that EVs at 100μg/ml can significantly promote the proliferation and synthesis of androstenedione and progesterone in ovarian cortical stromal cells. This research is of great significance for further elucidating the regulatory role of follicular fluid EVs in follicular development and atresia and for research on the interaction of ovarian stromal cells, granulosa cells and oocytes.