In this study, polymorphism in the exon 1, 2, 3, 4 and 5 of bovine GAD1 gene was detected by PCR-SSCP and DNA sequencing methods in 726 individuals from three Chinese cattle breeds. Two haplotypes (T and C) and three observed genotypes (TT, TC, and CC) were detected. The result of DNA sequence showed one mutations (T12345C) by comparisons with NC_007300: g.12345T>C. The mutation was at the exon 3, and was identified a missense mutation Phe (TTT)>Leu (CTT) at position 51 (p.F51L). Polymorphism of the GAD1 gene was shown to be associated with growth traits in the Nanyang breed. The SNP in the bovine GAD1 gene had significant effects on body length, body weight, heart girth, and average daily gain at 24 months (P < 0.05). Therefore, these results suggest that the GAD1 gene is a strong candidate gene that affects growth traits in cattle.