Objective:To probe the expression of miR-126 and VEGF in breast cancer, and the anti-tumor effect of miR-126. Methods:The expression of miR-126 and VEGF in breast cancer tissues and cells were detected by qRT-PCR and Western blot;after transfection with miR-126 mimics into MDA-MB-231,expression of VEGF was detected again,MTT assay and cell scratch test were used to verify the influence of miR-126 on proliferation and migration of tumor cells. Results: The expression of miR-126 was lower in the breast cancer tissues and cells,the expression of VEGF was negative correlation with it,increasing the expression of miR-126 may decrease the expression of VEGF and inhibit the proliferation and migration of breast cancer cells. Conclusion:miR-126 can reduce the proliferation and migration of breast cancer cells by inhibiting the expression of VEGF,which play an anti-tumor effect.