In this study, we analyzed the amino acid contents of corn to provide basic data for promoting the use of proteins in livestock. The present study was done to examine the amino acid contents of the corn ‘Gwangpyungok’ grown in a natural field at the National Institute of Animal Science, Cheonan province, Korea, in 2016. Gwangpyungok, which is Korean corn cultivar, was used as the sample to provide basic data for promoting the use of proteins in livestock by analyzing the amino acid contents of each part of corn as a breed that is adaptable to the environment of Korea. The asparagine acid content was the highest in the leaf blade among the parts of corn, and the glutamic acid content was the highest in the corn ear, stem, leaf sheath, corn bract and inflorescence. The essential amino acids in the corn ear, leaf blade and inflorescence revealed that their contents were in the following order: leucine > phenylalanine > valine > threonine > lysine > isoleucine, and in the inflorescences and stem, leaf sheath and corn bract, their contents were in following order: leucine > valine > phenylalanine > threonine > lysine > isoleucine. Therefore, further research on the nutritional aspects of forage must be performed because livestock growth is influenced by the nutritive value of the various parts of forage.