Abstract:In order to explore the genetic diversity and geographical origin of Amomum tsaoko, the genetic variation of A. tsaoko and A. paratsaoko in 8 SSR loci was studied. The results showed that there was 149 and 101 alleles were detected at 8 SSR loci from 20 populations of A. tsaoko and 5 populations of A. paratsaoko respectively, among which 44, 59 were unique alleles. Variance analysis (AMOVA) showed that only 10.43% of genetic variation existed between two species, 8.66% between populations, and 80.91% within populations (P<0.01). The total genetic differentiation of A. tsaoko was moderate (0.05 ≤ Fst ≤ 0.15), and A. paratsaoko was high (0.15 ≤ Fst ≤ 0.25). The genetic differentiation of the two species increased under SMM model (Fst<Pst). Therefore, the genetic diversity of two species shared the same ancestry, and it was possible that the existing genetic differentiation pattern had been formed by the accumulation of mutations after lineage sorting through random genetic drift. So, Maguan and Pingbian areas around Dawei Mountain might be the geographical origin center of A. tsaoko cultivation.