Most of the walnut trees grown in Turkey have been obtained from seeds and show great variability. Humans selected the best seed-propagated ones and kept them in the field. This precious walnut germplasm could be potentially interesting either to directly register them as cultivar or to use them in walnut cross-breeding studies as parent to improve some characteristics of cultivars. This study assessed the genetic diversity of 28 seed propagated walnut genotypes grown in Gumushane province in Turkey using 21 polymorphic walnut SSR markers. Among the used germplasm 129 alleles were detected. Allele number ranged from 2 to 13 and the average allele number was 6.15 alleles per locus. There were no identical genotypes in the dendrogram. Present results revealed that the studied walnut germplasm is genetically variable. This could be important for future cross-breeding activities.