Abstract:Eight geographic populations of the scale insects,Eulecanium kuwanai Kanda and Eulecanium gigantean Shinji,in Hebei Province were investigated by RAPD-PCR techniques for the determination of their genetic structures. Samples with 10 adults were examined for each population. Sixty five RAPD makers were found by using five selected primers. No specific band was observed for any population. The distance analysis shows that the similarity within an intraspecies population is higher than that of interspecies; the genetic similarity among different populations is inversely proportional to their geographic distances. Shannon′s index showed that the average genetic diversity within populations in Eulecanium kuwanai Kanda was higher than that in Eulecanium gigantean Shinji, with a value of 0.3456 and 0.3225, respectively, demonstrating that the degree of genetic variation was diverse among different species.