Knowledge of genetic variation is needed to understanding the genetic structure in forest tree populations. In addition, the determination of the genetic structure in the natural distribution areas of forest trees has become easier depending on the development of the isoenzyme technique. Determining the genetic structure and variations of Picea orientalis (L.) Link, which is limited local natural distribution areas on the world, transfer of this genetic to the future generations with sustainable forestry is important to ensure the continuity of the species. In this study, genetic differences and similarities were determined for P. orientalis populations in selected regions (Artvin, Torul-orumcek, Tirebolu-Akilbaba, Ordu-cambasi, Artvin-Savsat, Ardanuc-Ovacik, Savsat-Sahara, Artvin-Sacinka, Ardahan-Posof and Macka-Hamsikoy) in Turkey. In the study using 10 gene loci in different enzyme systems to determine the genetic variation, the values of heterozygosity (H-o), number of alleles per locus (A(L)), genetic diversity (v), intrapopulational differentiation (d(T)), multilocus diversity (V-gam) and differentiation among populations (Dj) were determined in these populations. The grand means were obtained as 0.154, 1.74 and 1.719 for the observed heterozygosity, alleles per locus and genetic diversity, respectively. Moreover, when the genetic diversity was considered, three different groups arose in terms of selected populations. Since Torul-orumcek population had relatively higher results in contrast to other populations, this population has high importance for sustainability of gene resource of oriental spruce.