Abstract: Recent developments in DNA technologies have made it possible to uncover a large number of genetic polymorphism at the DNA sequence level and to use them as markers for evaluation of the genetic basis for the observed phenotypic variability. The use of DNA markers to define the genetic makeup (genotype) and predict the performance of an animal is a powerful aid to animal breeding. Molecular markers are a tool to study the diversity on the genetic level. The ultimate use of DNA markers would be to identify Quantitative Trait Loci (QTL) in order to practice genotype selection. In recent years different marker systems such as RFLP, RAPD, STS, AFLP, SSR, SNP and other have been developed and applied to livestock. This study provides a brief overview of the current application of these markers in animal breeding.