Maize is an important food crop that is primarily used as feed to provide necessary metabolizable energy and nutrients for livestock and poultry. The nutritional value of feed is closely associated with the proportion of protein and amino acid composition; however, corn protein exhibits an imbalanced amino acid content, particularly a low concentration of methionine, which serves as the second limiting amino acid. The nutritional value of feed is closely associated with the proportion of protein and amino acid composition; however, corn protein exhibits an imbalanced amino acid content, particularly a low concentration of methionine, which serves as the second limiting amino acid. In recent years, extensive research has been conducted on the absorption and transport mechanism of sulfur elements in plants, leading to the initial construction of a metabolic regulatory network for sulfur-containing amino acids. In this study, we summarized the research results of improving the mechanism of sulfur-containing amino acids in crops, proposed a new strategy of combining population genetics, comparative genomics and molecular biology to mine candidate genes, and used modern biological breeding to improve the methionine content of corn grains, so as to provide a reference for genetic improvement of high-quality protein maize.