The construction core collections allow for more efficient use and management of genetic resources, and has been proposed as an efficient method for conducting intensive investigations into natural variation, including phenotyping of complex traits and genotyping of DNA polymorphisms. In this study, 614 Korean core set of wheat (Triticum aestivum L.) were established from 1,969 germplasm from about sixty countries of Asia, Europe, America, Africa, Eurasia and Oceania, etc., and the agronomic traits was investigated during 2018-2021 in Korea. Then genome-wide association study (GWAS) was performed with the genotyping data used ‘Axiom Wheat Breeder 35K Genotyping Array’ to identify loci associated with agronomic traits of hexaploidy wheat (Triticum aestivum L.) grown at Wanju in South Korea. The correlation between the genotype and the phenotype was performed for each model of Blink, MLM, and MLMM, and SNPs with a result that satisfies threshold P-value of -log10 of 5 or more were selected was used to declare significant SNPs for GWAS results. The 94 SNPs of approximately 35,000 SNPs of genotyping results were selected as candidate markers associated with several agronomic traits including yield components and growth characters. Further studies are needed to detect SNP markers using population and environment.