Simple sequence repeat(SSR) markers were used to estimate the genetic structure and diversity of seven populations of Elaeagnus mollis,an endangered plant from the Shanxi and Shaanxi provinces,China.Ten pair primers generated a total of 126 reproducible and discernible loci,among which 114 were polymorphic.At a species level,the proportion of polymorphic loci was 90.79%.The effective number of alleles(Ne
) was 1.6072,Nei’s gene diversity index(H
) was 0.3166,and the Shannon index(Ⅰ) was 0.4603.At a population level,the proportion of polymorphic loci was 61.99%,Ne
=0.2683,and Ⅰ=0.3815.The coefficient of gene differentiation(Gst
=0.2074) showed greater genetic variations occurred within the population than among populations.Gene flow(Nm
) was 1.9111>1,which showed that gene interflow occurred among populations,and that genetic differentiation was prevented due to genetic drift.Cluster analysis showed a certain correlation between genetic distance and geographic distance.Mantel test showed a positive correlation between geographic distance and genetic distance,but did not reach a significant level(p>0.05).The results showed that genetic diversity was related to species traits and habitat disturbance.The endangered plants did not necessarily display a lower level of genetic variation.