The aim of this research was to determine the genetic structure of Turkish fat-tailed sheep breeds (Akkaraman, Guney Karamam, Morkaraman, Daglic, Ivesi, Karakas, Tuj and Norduz) using RAPD (Random Amplified Polymorphic DNA) markers. By using 12 RAPD primers in 125 sheep obtained 218 polymorphic loci which were determined. Average allele number (n(a)) average effective number of allel (n(e)) average heterozygosity (H), average expected heterozygosity (h(j)) Shannon's constant (H-0), polymorphic loci number (n(p)) and polymorphic loci ratio (P-poly) were found as 2.00, 1.6256, 0.3636, 0.1784, 0.5408, 218 and 100 %, respectively. Used to determine genetic differences between sheep population; genetic diversity coefficient (H-T), average heterozygosity within populations (H-S) and total heterozygosity were found as 0.5117, 0.1784 and 0.3654, respectively. Genetic distance between sheep populations (D) was changed from 0.1349 to 0.5563. According to cluster analysis result, Akkaraman, Guney Karaman and Morkaraman created a cluster, Tuj breed was more close than Ivesi to first cluster. Daglic and Karakas took place another cluster. Norduz breed appeared to be most distance from other sheep breeds.