The spatial distribution of nitrogen (N) in different vertical distribution leaves is considered to be an important adaptive response of crop growth and production. Accordingly, remote sensing has been widely used for monitoring the crop N status. Nevertheless, the impacts of the type of plant geometry on the detection of the N vertical distribution of the maize canopy by canopy spectral reflectance remain poorly understood. In this study, treatments of three types of maize plants (horizontal, intermediate and upright leaf varieties) were conducted to understand how the type of plant geometry influences the remote estimation of the N nutrient status in lower layer leaves at different growth stages. The results revealed that different types of maize plants were significantly different in canopy architecture, vertical distribution of canopy N and the detectability of lower leaf N density (LND) within a canopy by canopy spectral reflectance. The upright leaf variety performed the best in estimating the lower LND (R²=0.52) by the best new simple ratio (SR) index (736, 812), which was also suitably applicable to estimate the upper (R²=0.50) and middle (R²=0.60) LND. However, only 25% of the variation in the lower LND of the intermediate leaf variety was explained by the best new SR index (721, 935). The horizontal leaf variety showed little spectral sensitivity with the lower LND. Besides, the growth stages also had an influence on the remote detection of the lower leaf N status of the canopy, due to biomass dominating canopy reflectance before V12 growth stage (12 collars) and after it instead of the plant N. Therefore, we can conclude that maize with upright leaves makes it feasible to detect the N nutrition status of the lower leaves by canopy spectral reflectance.