The canopy spectra under different levels of nitrogen was used to study the nutritional status of nitrogen. The aim is to find out the relationship between bio-chemical parameters (chlorophyll-a content, chlorophyll-b content, chlorophyll content, sum nitrogen, protein content, fibre content, sheath amylum) and the characteristic variables of hyperspectra on rice field. The results show that the correlation between chlorophyll-a and chlorophyll content and the characteristic variables of hyperspectra is reduced while the position of the leaves are shifting from top to bottom. There are relationships between the characteristic variables of hyperspectra(such as the green peak or red valley of reflectivity, the red edge position, the blue edge area and the vegetation indices), and chlorophyll-a content and chlorophyll content of up leaves and fibre content, and sheath amylum in leaves. However, the relationship between the characteristic variables of hyperspectra and protein content in leaves cannot be found.