Objective：To investigate the proliferation and migration effect of cortisol on hormone-related breast cancer MCF-7 cells. Methods：MCF-7 cells, originated from a hormone-related breast cancer woman, were treated with different concentration of cortisol. The effect of cortisol on cell proliferation was determined by MTS assay and the rate of cell survival was calculated. The effect of cortisol on cell migration was examined by wound-healing assay.Immunoblot analysis detected the protein expression of phospho mTOR (p-mTOR)， which is involved in cell proliferation，and MMP-9, MMP-2，which are related to cell migration. Results: Cortisol at concentration of 10 nmol/L significantly increased cell proliferation（P<0.05）and cell migration（P<0.01）compared with the vehicle group. Furthermore, cortisol at concentration of 10 nmol/L obviously increased the protein expression involved in cell proliferation (pmTOR，P<0.05) and cell migration (MMP-9, P<0.05； MMP-2，P<0.01). Conclusion: Cortisol at concentration of 10 nmol/L effectively induced cell proliferation and cell migration by activating mTOR pathway and upregulating MMP-9 and MMP-2 protein expression.