There are many properties for herbs. One of these properties is meridian tropism theory. It is also an important concept in Chinese Medicine Pharmacology. In this study, we try to extract the microcirculatory property of acupoint and meridian to study the effects of taking Liu-Wei-Dihuang. In the experiment, we use Laser Doppler flowmetry (LDF) to monitor microcirculation. The measurement site are Tai-Xi (Ki3), nonacupoint near Tai-Xi, and He-Gu (Li4). We also do blank test to contrast with the experiment of taking Liu-Wei-Dihuang. The result of this study indicates that Liu-Wei-Dihuang increase the blood flow at Tai-Xi, and make the variation of blood flow at Tai-Xi larger than it is in the blank test. This phenomenon imply that Liu-Wei-Dihuang may improve the microcirculation of lower extremities.