Abstract:Inter-simple sequence repeats 0SSR)marker was used to analyze the genetic diversity and diferentiation of 137 individuals within and among 7 populations of Orchidantha chinensis，an endan gered species，in Guangdong Province．Ten ISSR primers generated 101 bands，ofwhich 58(57.43％)were polymorphic．ISSR diversity within the population was lower than that among the populations(at species level：P=57.43％，H=0.1254，I=0.2000；at population level：P=18.24％，H=0.057，I=0.0876)．Based on Nei’s GST value calculated by POPGENE1．3 1，gene diversity within populations was 0.1 254±0.1686．Shannon information index was 0.2000±0.2429．Variation coeficient among populations was O.5481, and that within population was O.4519．The ranger ofgentic identity among populations was from 0.8855 to 0.9511. Based on the gene diversity inform ation available for Orchidantha, two management strategies are proposed．A conservation area is suggested to be established in Honghuatan(HHT) where is considered to be an optimal habitat for O.chinensis growth．And because ofthe diferentiation among the populations， cross transplan tation is suggested in order to enhan ce the gene flow among the populations． By this means，the genetic diversity resources of the species could be preserved to the greatest extent.