Objective: To investigate the expression of vascular endothelial growth factor (VEGF)and the significance of matrix metalloproteinases-9 (MMP-9), which is modulated by VEGF, in the invasion of gastric carcinoma. Methods: Expression of VEGF in gastric carcinoma and normal gastric tissues was detected by Western blot. MTT was used to measure the proliferation of AGS cells while real-time PCR and Western blot were used to measure the expression of MMP-9 at mRNA and protein level in AGS cells. Results: The expression of VEGF in gastric carcinoma was significantly higher than that of controls; the expression of MMP-9 in AGS cells with VEGF was significantly higher than that of controls at mRNA and protein level. Conclusion: Both VEGF and MMP-9 participate in the progression of gastric carcinoma, and VEGF may promote the invasion of gastric carcinoma by upregulating the expression of MMP-9.