Abstract: This study is to investigate the effect of ethyl gallate on invasion capabilities and its mechanism of breast cancer MDA-MB-231 cells. Using cell adhesion and transwell assay, separately, the effects of ethyl gallate on the invasion of MDA-MB-231 cells were measured. The Akt-NF-κB signal pathway protein expressions were analyzed with Western blot. Also, the mRNA levels of MMP-9 and MMP-2 were analyzed by RT-PCR. Ethyl gallate inhibited the abilities of motility, adhesion and invasion of breast cancer MDA-MB-231 cells in vitro (P < 0.05), inhibited the mRNA levels of MMP-9, MMP-2, phosphorylation of AKt and protein expression of NF-κB. It is concluded that ethyl gallate can inhibit the abilities of invasion of breast cancer in vitro by inhibiting the mRNA levels of MMP-9/MMP-2, phosphorylation of Akt and protein expression of NF-κB.