Abstract: <b<Objective</b< To study the feasibility of 16-sice CT angiography with low dose contrast agent in the lower extremity. <b<Materials and Methods</b< Sixty-six patients with lower extremity 16-slice CT angiography were divided into 3 groups according to the dosage of contrast agent as follows:150ml,120ml,and 80ml.Each group was graded by using source image and MIP reconstruction for vascular delineation of lower extremity artery. <b<Results</b< The lower extremity artery in all groups were well delineated and there were also no significant difference statistically among the three groups on subjective graded scores.CT attenuation values in the artery were high,and with no significant difference among three roups. <b<Conclusion</b< It is feasible to use low dose contrast agent with 16-slice CT angiography in low extremity.