Abstract: From 1996 to 1997,the effect of applying organic and chemical fertilizers on NO₃^- and NO₂^- accumulation in crop seeds was studied in four green food bases of kidney beans (Yunan Province),red small beans (Hebei Province),soybeans (Heilongjiang Province), and peanuts (Shandong Province).For kidney beans and red small beans,the highest grey correlation was existed between available N in soil and NO₂^- in seeds,no matter whether organic fertilizer or urea was applied.In organic fertilizer trials,the highest grey correlation appeared in soil pool (between total N and available N)or seed pool (between NO₃^- and NO₂^-),while in chemical N fertilizer trials,it existed between total N in soil and NO₃^- in seeds.For kidney beans and red small beans,the dynamics of NO₃^-/NO₂^- in seeds was different with the kind of fertilizers applied. Extremely significant negative linear correlation and positive linear regression were existed between the content of NO₃^- and NO₂^- in all four crop seeds.