The objective of this study is to investigate the regulatory mechanisms of sugar metabolism in maize stalks at varying planting densities. Targeted metabolomics and transcriptomics analyses were performed on stem samples of two varieties (M1 B12 and M2 J1590) at two planting densities (105,000 plants ha -1 and 135,000 plants ha -1 ) during the tasselling stage and grain filling stage. Combined with bioinformatics methods, these analyses elucidated sugar metabolism-related metabolites, gene expre