The effects of Aster scaber and Ixeris dentata on cadiovascular system in hyperlipidemic rats were examined. Five groups of thirty Sprague Dawley rats were fed with the diet contained 1% cholesterol, 0.25% sodium cholate, 10% coconut oil and 5% lard(control group) for 4 weeks. Each experimental diet group was added with 5% plant powder or extract of the 5% plant powder by dry weight. Contractile or relaxation responses in the isolated artria and thoracic aortae were measured and the morphological changes of the aortic endotherium from the rats fed the experimental diet were inspected. In response to isoproterenol, the number of right atrial spontaneous beat was significantly lower in Cham chyi powder group$(PP_{1})$ and Sumbagui powder group$(PP_{2})$ than control at $10^(-8)M$ concentration. The contraction forces by injection of phenylephrine and calcium in isolated thoracic aorta were significantly low in each experimental groups compared with the control. The relaxation rates by acetylcholine represented comparatively higher value in $PP_{1}$ than control. The morphological changes of endothelial cell surface was a little in $PP_{1}$ and $PP_{2}$ compared with control, while the damages were considerably advanced in Cham chyi and Sumgbagui extract diet group$(PE_{1},;PE_{2})$.