The paper aims to measure the canopy hyperspectral reflectance and the content of chlorophyll aand b at the stage of budding, flowering and maturity under different nitrogen levels respectively, and study therelationship between the spectra and the content of chlorophyll, by taking the early maturing rapeseed variety‘420'as the raw material. The results showed that: under different nitrogen levels, all of the rape canopyreflectance spectra had the same trend, the parameters of chlorophyll content and spectrum showed asignificant positive cor...