Abstract: Abstract: Nitrogen (N), phosphorus (P) and potassium (K) are the necessary nutrients for the plant growth. To save the cost and minimize ecological impact of fertilizer application, it is important to use variable rate of fertilizer management to address differences in plant nutrients requirements. The objective of this study was to develop a model to predict winter wheat and maize N, P, and K uptake based on canopy spectral reflectance from a long-term fertilizer experiment in Huang-Huai-Hai area. The relationship between total N, P, and K uptake at harvesting stage and canopy spectral reflectance of winter wheat and summer maize at four typical growth stages were established so that plant nutrient uptake can be predicted based on the spectral reflectance. The results showed that the reflectance value of summer maize were similar to the value of winter wheat in visible light at the corresponding stages, but its average was 8.42% higher than winter wheat in near- infrared region. There were significant negative correlations between main nutrients uptake of crops and canopy spectral reflectance, in contrast, there were significant positive correlations between those at near-infrared region. The average correlation coefficients between the reflectance of summer maize and N uptake were similar to winter wheat at visible light at whole stage, but it was 0.4125 higher than winter wheat in near-infrared region. The average correlation coefficients between the reflectance of summer maize and P uptake were 0.3621 and 0.2072 lower than winter wheat at visible light and near-infrared region, respectively. The average correlation coefficients between the reflectance of summer maize and K uptake were 0.1270 lower than winter wheat at visible light, and it was 0.0341 higher than wheat winter in near-infrared region. Then, the stepwise regression was used to generate equations for the estimation of major nutrients requirement of winter wheat and summer maize from the canopy reflectance. The results showed that except for P uptake of summer maize, other major nutrients uptake of two crops could be predict at four different growth stages. The results can provide a tool for nutrient management of winter wheat and summer maize in Huang-Huai-Hai region of China.