Abstract: To explore the genetic diversity of Gleditsia sinensis. The genetic diversity of 203 samples from 14 natural populations of G. sinensis in Guizhou Province was studied by using related series amplified polymorphism(SRAP) molecular marker technology. Cluster analysis was used to explore the correlation of Nei's genetic identity or genetic distance and geographical distance among G. sinensis populations. The results showed that 77 clear bands were amplified by 10 pairs of SRAP primers, and the polymorphism ratio was 98.70%. The selected SRAP primer combination had good polymorphism and could be used for the genetic diversity analysis of G. sinensis. The number of observed alleles(N_a), effective number of alleles(N_e), Shannon information index(I) and Nei's genetic diversity index were 1.7922, 1.5613, 0.4633 and 0.3174. The genetic differentiation coefficient(G_st) among the G. sinensis populations was 0.2530, and the gene exchange value(N_m) was 1.4764. There was strong gene flow among the populations, and the differentiation was small; the population genetic distances ranged from 0.0504 to 0.3596, with an average of 0.162. Geographical distances were positively correlated with genetic distances. Cluster analysis showed that the 14 groups could be divided into 4 groups; among them, Fuquan in Qiannan was regarded as a group alone.