Abstract:The objective of this study was to determine the effect of different N rates on yield and quality parameters of high grade yellow seed hybrid rape.The results showed that nitrogen fertilizer had significant influence on oil content,erucic acid,glucosinolate,seed proteins of the high grade hybrid rapeseed and had no influence upon oleic acid.For the influence on linoleic acid,linolenic acid and arachidonic acid,the significance differed among various types.There were significant negative correlations between oil content,glucosinolate,linoleic acid and nitrogen rate,and significant positive correlation between erucic acid,seed proteins,arachidonic acid,linolenic acid and oleic acid and N rate.The correlation between each quality parameter of different types and N rate was similar,only differing in significance levels.Oil content was negatively correlated with seed proteins.Erucic acid was positively correlated with seed protein,linolenic acid and arachidonic acid.Glucosinolate was negatively correlated with seed proteins,positively correlated with linoleic acid.Seed proteins were positively correlated with arachidonic acid.The correlations among other quality parameters were similar,only differing in significance levels.The optimum N rates for maximum yield and oil yield under the conditions of this study were 210 kg/ha and 195 kg/ha respectively.When maximum yield was obtained,high quality could be guaranteed.