An exponential fertilization experiment was conducted with six dose levels(applying a total of 0，100，200，400，600，800 mg/plant in this experiment) of nitrogen to assess the effects of different nitrogen levels on the growth and foliar nutrient status of pecan seedlings.The objective of this study was to reveal the nitrogen demand and determine the optimal nitrogen amount for pecan seedlings.Results indicated that:(1)the height，ground diameter and biomass of pecan seedlings increased as the nitrogen fertilization increased from 0 to 600 mg/plant and then decreased when the nitrogen fertilization increased from 600 to 800 mg/plant．The maximum values were 33.4 cm,5.08 mm and 9.33 g/plant,respectively．Critical level approach was used for identifying N，P and K deficiencies by means of foliar analysis in pecan seedlings，and the critical values of N，P，and K were 22.58，1.89 and 12.71 g/kg,while their optimal concentrations ranged from 22.58 to 32.73,1.89 to 3.15,12.72 to 22.05 g/kg,respectively.Based on these results,it could be inferred that 600 mg/plant would be the optimal nitrogen amount for pecan seedlings．