Abstract: The allozymic loci genetic diversity in Manglietia patungensis Hu, a threatened and endemic species, was examined employing isoelectric focusing in thin-layer polyacrylamide slab gels. Eighteen loci of eight enzymes systems were detected and used to estimate levels of genetic diversity within and among populations. The results revealed high levels of genetic diversity in M. patungensis. Twelve of the 18 loci scored were polymorphic （P_s=66.7）, and the mean expected heterozygosity （H_e） was 0.178, which were higher than those of other long-lived woody plants. The F_st, a parameter measuring the differentiation among populations, was 0.107 suggesting 89.3% of its genetic differentiation distributed within populations.