Sorghum [Sorghum bicolor (L.) Moench], a cereal crop of family Poaceae, is believed to be originated in Ethiopia and Sudan. It is an important food security crop mainly in semi arid and tropical parts of the African countries. Although many morphological and molecular diversity studies reveal the existence of genetic bvariations with sorghum populations, their distribution within basic races were not considered. Hence, the present study aimed to analyze the extent and distribution of genetic variation within basic Ethiopian sorghum landraces using SSR markers. A total of 107 landraces obtained from Ethiopian Biodiversity Institute (EBI) representing 12 ecological zones grouped according to their race types based on inflorescence and spiklet on field at their maturity time. Twelve SSR markers revealed a total of 110 allelesrnwith average polymorphic content of 0.76 and the allele frequencies shows 42 of allelesrnwere rare (less than 0.05), 22 ranged from 0.05 to 0.1, while 46 of them were higher thanrn0.1. Expected and observed heterozygosity were 0.78 and 0.2 respectively. The geneticrndifferentiation between populations were also moderate (FST=0.07 for races and 0.13 forrnE/zones) indicating continuous exchange of genes among them. Partitioning the totalrngenetic variation also indicated 61.38% and 55.17% of the variations were amongrnindividuals within racial and zonal populations respectively. Neighbor-Joining clusterrnanalysis also indicated four major grouping of the landraces according to their racialrngroups where majority of race caudatum and durra form separate groups whilernintermediate durra-bicolor form two separate sub-clusters. Overall locus the intra-racialrnpopulation diversity showed the greatest genetic diversity (He=0.77 and 0.75) amongrnrace bicolor and caudatum respectively. Information with sorghum races along theirrnimportant agronomic traits could be used for conservation and future breeding programsrnof sorghum.rnrnKey words: Sorghum bicolor; races; Genetic diversity;SSR