Limited geographic area and focused modification of rapeseed during of its breeding cases have been led to the limited genetic basis. So, the evaluation of genetic diversity in modern cultivars of canola to estimating and maintain of genetic resources is essential. In this study, the genetic diversity of 45 genotypes of rapeseed was investigated using 12 RAPD markers .Cluster analysis by Dice coefficient and non-nearest neighbor method (NJ) divided genotypes into seven main groups. The total variation was 0.662. Polymorphism information index (PIC) was from 0.158 to 0.483 and mean of 0.346. The total number of alleles amplified was 68 with average of 5.66 alleles per marker. The percentage of polymorphism for all markers was one hundred percent. These markers could represent a unique band for Oligo 213 primer in Hyola 420 genotype. It seems that more attention to genetic diversity of studied genotypes, based on primers used can use as a source for further research in modification of rapeseed to achieve goals such as more heterosis in hybrids.