This study was conducted to determine DNA-polymorphism of a AluI RFLP at bovine growth hormone (bGH) gene in Zavot (n=48), East Anatolian Red (n=40), Simmental (n=94) and Brown Swiss (n=64) cattle breeds. A total of 246 cattle were genotyped for the bGH-AluI polymorphism by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). In the study, two alleles (L and V) and three genotypes (LL, VV and LV) were revealed after than digestion of amplification product with AluI restriction enzyme. Allelic frequencies for EAR, SIM, BS and Zavot breeds were determined as 0.775, 0.734, 0.781 and 0.760 respectively for L allele; 0.225, 0.266, 0.219 and 0.240 respectively for V allele. Otherwise, genotypic frequencies were 0.65, 0.57, 0.63 and 0.63 for LL, 0.10, 0.11, 0.06 and 0.10 for VV, and 0.25, 0.32, 0.31 and 0.27 for LV respectively. A significant deviation from Hardy-Weinberg equilibrium was not observed in the investigated breeds. As a result, this study provided information on the polymorphism of bGH in four cattle breeds. Additionally, this study reported the existence of a genetic polymorphism at bGH gene in Zavot cattle breed for the first time.