Field experiments of summer maize (Zea mays L.) were conducted in 2005 and 2006. By measuring and observing aboveground chlorophyll and total N contents and canopy reflectance, incorporating the crop growth property and absorption for nutrients at six different growth stages, analyzing the relationship between the single reflectance, vegetation indices and chlorophyll, total N, several N uptake and utilization indices in details. The results showed that there was the highest reflectance in near infrared and the lowest reflectance in visible region at booting stage; correlation between NDVI and the contents of chlorophyll and N increased from seedling to booting stages, then decreased at tasseling and silking stages, and increased at filling stage. On the whole, there was best relationship between GNDVI (560,760) and agronomic parameters at different growth stages, the second was NDVI (660,760). NUE, NHI, NAE and ARF all deceased with the increase of N fertilizer amount, and NDVI (660,760) and GNDVI (560,760) were better to predict the N uptake and utilization efficiency. These results indicated that canopy spectral reflectance can be used to monitor non-destructively leaf chlorophyll and N status in summer maize.