The randomly amplified polymorphic DNA (RAPD) analysis has been applied for estimating genetic diversity in plant populations or cultivars. To discriminate geographical origin among Astragali radix populations, RAPD analysis was carried out using 20 mer-random primers. The similarity coefficient between the DNA of Astragali radix plants analyzed was 0.527. Although the coefficients of similarity were high, primer 7, 8 and 10 gave distinguishable bands between Korean and Chinese Astragali radix. We obtained the specific RAPD markers to discriminate between Korean and Chinese Astragali radix at a DNA level. These results suggest that this method is able to discriminate the concerned Astragali radix geographical origin species. Also, this is the first report on the genetic diversity in geographical origin among Astragali radix populations using RAPD analysis. Broader application of this approach to authenticate other morphologically similar medicinal materials is rationalized.