In this study, Mesocricetus brandti (Nehring, 1898) specimens collected from different area of Anatolia (Sebinkarahisar, Bolkar Mountain, Aksaray, Ardahan, Van) and Iran- Zanjan were examined. Chromosomal arrangements of these individuals were analyzed by using colchicine- hypotonic citrate karyotype technique. Diploid chromosome numbers of whole specimens were determined to be the same, being 2n=42; however fundamental number of chromosomal arms (FN) of these specimens had two forms; being FN=84 and FN=82. These two forms were mated in laboratory conditions and hybrid individuals (both male and female) obtained from interbreeding specimens of Zanjan (Iran) which has 84 FN and Bolkar Mountain (Nigde, Turkey) which has 82 FN. It is determined that, these hybrid individuals have 83 chromosomal arms (FN) and one of homologous chromosomes of the 20 th autosomal pair is acrosentric and the other is metacentric.