The MC1R (Melanocortin 1 receptor) gene has been known as a causative gene of the coat colors in mammals and responsible for the E (Extension) locus which has three alleles ($E^D$, $E^+$, e) that determines coat colors. The dominant allele $E^D$ produces black or brown colors due to the missense mutation and the recessive e allele has frameshift mutation which shows red or yellow coat colors. Whereas the wild type $E^+$ produces variety of colors due to the interaction with A (Agouti) locus. In this study, PCR-RFLP was performed using two restriction enzymes (BsrF I and MspA1 I) in order to obtain MC1R genotypes in Korean brindle cattle and black cattle. The results showed that all of the animals have the $E^+$ alleles, indicating the $E^+$ allele might related with black coat colors. Later on, the experiments expanded to the 260 Korean candidate bulls whether these animals have the same $E^+$ allele. Among 260 samples investigated, 5% (13/260) of the animals had $E^+$e genotypes, indicating the $E^+$ allele is also present in the candidate bulls in a low frequency. Even though we expected that A locus also affect the black coat color in cattle, all the black coat color animals (brindle and black) have $E^+$ alleles in this study. Therefore, the genotyping of the MC1R gene in candidate bulls will recommended be applied for eliminating of black coat colors in Hanwoo population, if the farmers need to have the brown coat colors only.