Abstract: Abstract: An additive-dominance-maternal genetic model with genotype by environment interactions by Zhu Jun were applied to analyze genetic main effects and genotype by environment interactions for leaf protein content in maize under different environment conditions and different developmental stages. The results indicated that at different developmental stages the leaf protein content in maize was significantly effected by different genetic effects as well as by different environment interactions, so it was very important to pay attention to the different of genetic effects under different developmental stages and different environments. Key word: Maize; Protein; Genetic effect; Genotype by environment