Abstract：Purpose To investigate the function of RhoE in metastasis of human gastric cancer and possible mechanisms. Methods Immunohistochemistry and Western blot (WB) were used to analyze the protein level of RhoE in gastric cancer tissues. Protein and mRNA of RhoE were separately examined by Western blot and semi-quantitative PCR in two human gastric cancer lines with different metastatic potentials. Plasmid encoding RhoE and empty vector were transfected into SGC7901 cells through stable transfection. Wound-healing assay and invasion assay were used to examine the in vitro migratory and invasive abilities of the transfected cells and control cells. Western blot analysis was performed to examine the changes of MMPs. Result RhoE expression was highly related to the metastasis of gastric cancer. Upregulation of RhoE significantly enhanced cell migratory and invasive abilities in vitro, and upregulated MMP9 rather than MMP2. Conclusion RhoE could enhance the metastasis of gastric cancer through upregulating MMP9.