Objective: The objective of the present study was to validate genes and genomic regions associated with carcass weight using a low density SNP Chip in Hanwoo cattle breed. Methods: Commercial Hanwoo steers (n=220) were genotyped with 20K GeneSeek genomic profiler BeadChip. After applying the quality control of criteria of a call rate ≥90% and minor allele frequency (MAF) ≥0.01, a total of 15235 autosomal SNPs left for genome-wide association analysis. Genome-wide association (GWA) tests were performed using single-locus mixed linear model. Age at slaughter was fitted as fixed effect and sire is included as covariate. The level of genome-wide significance was set at 3.28 x 10-6 (0.05/15235), corresponding to Bonferroni correction for 15235 multiple independent tests. Results: By employing EMMAX approach which is based on a mixed linear model and account for population stratification and relatedness, we identified 17 and 16 loci significantly (P < 0.001) associated with carcass weight for the additive and dominant models, respectively. The second most significant (P = 0.000049) SNP (ARS-BFGL-NGS-28234) on BTA4 at 21 Mb had an allele substitution effect of 43.45 kg. Some of the identified regions on BTA2, 6, 14, 22, and 24 were previously reported to be associated with quantitative trait loci (QTL) for carcass weight in several beef cattle breeds. Conclusion: This is the first genome-wide association study using the SNP chips on the commercial Hanwoo steers, and some of the loci newly identified in this study may help to better DNA markers that determine increased beef production in commercial Hanwoo cattle. Further studies using large sample size will allow confirmation of the candidates identified in this study.