Objective: To study the influence of vascular endothelial growth factor(VEGF) expression on angiogenesis,the relationship of VEGF expression and microvessel density (MVD) with invasion and metastasis of colorectal carcinoma.Methods: Sixty-one samples of colorectal carcinoma tissues were examined for VEGF expression by SABC immunohistochemical method and for the CD34 endothelial antigen by SP immunohistochemical method to highlight the new growth microvessels,the MVD of tumor was calculated.Results: The positive expression rate of VEGF was 49.2% and the mean of MVD was 28.7?12.9 (range from 6 to 55) in colorectal carcinoma tissues.The positive expression rate of VEGF and MVD were significantly correlated with the depth of invasion,lymph node metastasis,liver metastasis and Dukes’s stage(P29) was significantly higher than that in group of lower MVD.MVD in group of VEGF positive expression was significantly higher than that in negative expression group (P