Abstract： Objective To evaluate the correlation of 64-multidetector-row CT (64MDCT) perfusion imaging with microvessel density(MVD)and vascular endothelial growth factor(VEGF)in colorectal carcinoma. Methods 64MDCT perfusion imaging was performed in 33 patients with pathologically verified coiorectal carcinoma. Time-density curves(TDC) were created from the region of interest (ROI) drawn over the tumor, target artery and vein by 64MDCT with perfusion functional software. The individual perfusion maps generated were for blood flow(BF), blood volume (BV), mean transit time (MTT) and permeability-surface area product(PS). MVD and VEGF expression of surgical specimens were examined by immunohistochemical staining with anti-CD34, anti-VEGF monoclonal antibody. MVD and VEGF were compared among the different types of TDC in colorectal carcinoma. The correlation of CT perfusion parameters with MVD and VEGF was also examined. Results TDC of colorectal carcinoma was divided into five types according to their shapes. MVD in the colorectal carcinoma was 22.61±9.01. VEGF staining was found in 25 of 29 tumors (86.2%). The score of VEGF expression was 4.15±1.09. No significant differences of MVD and VEGF expression among TDC types were found (F=2.59, 1.11, P>0.05). There were also no correlations of MVD and VEGF expression with any dynamic CT parameters(P>0.05). Conclusion 64MDCT perfusion imaging, MVD and VEGF may reflect angiogenic activity, but no significant correlations are found among them.