This investigation was carried out at the Laboratory of Biotechnology at General Commission for Scientific Agricultural Research (GCSAR), during the season 2010-2011. The aim of this research was to study the genetic diversity among twenty individual plants of seven species and to determine the degree of genetic similarity using the technique ISSR (Inter Simple Sequence Repeats) and 10 primers were used for this purpose. All primers proved their effectiveness in showing polymorphism between the studied species, primers gave a total 195 allele with a polymorphic percentage 100%. The number of bands for each primer varied from a minimum of 12 bands for the primer (ISSR-4) to a maximum of 27 bands for the primer (ISSR-862) in an average of 19.5 bands for each primer, cluster analysis and Dendrogram showed the highest degree of genetic similarity between accession A.leucoclada1 and A.leucoclada2 (0.64), while it was low between species A.leucoclada3 and A.glauca2 (0.10). Results showed vast genetic diversity among the studied species.