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Knowledge about the amount of genetic diversity and understanding relationship between genotypes are important steps in plant germplasm conservation and breeding activities. In this study, the genetic diversity among 106 sunflower lines was assessed by 30 microsatellite primers. A total of 71 alleles were detected. Number of alleles in microssatellite loci ranged from 2 to 4 with the average number of 2.207 alleles per locus. The effective number of alleles ranged from 1.058 in locus ORS718 to 3.147 in locus HA3040. The average number of effective alleles was 1.641. The mean of PIC value was 0.344. Based on allele number and PIC value, SSR loci such as HA3040 and ORS733 are considered appropriate markers for studying genetic diversity in oily sunflower. Based on the results of cluster analysis using Jaccard's similarity coefficient and complete algorithm, the lines were grouped into four groups. Nineteen six out of 106 genotypes were grouped according to their origins (research centers). The highest and lowest Nei genetic distances were 0.21 and 0.004 between “NOVARTIS and HUNGARY” and “SPII with ENSAT and INRA-MONTPOL” groups, respectively. Analysis of the population structure revealed 5 subpopulations in the studied panel. The results show that the assignment of lines to subpopulations is not concordance with their geographical distribution pattern. The genetic diversity and distance revealed by SSR markers can be used in oily sunflower crossing and breeding programs