A solution culture experiment was conducted to study effects of NH₄⁺-N/NO₃^--N ratio on growth,food-safety and nutrition of spinach.The following results were obtained. (1) Fresh weight of spinach shoots gradually increased with the percentage of NO₃^--N in the total nitrogen,and spinach supplied with NO₃^--N as its sole nitrogen source was the highest in biomass,but there was no significant difference (p<0.05) in dry matter weight between treatments,25:75 and 0:100 in NH₄⁺-N/NO₃^--N ratio. (2) Contents of nitrate and nitrite in spinach shoots increased linearly with the decrease in NH₄⁺-N/NO₃^--N ratio.A significant quadric relationship was observed between the percentage of NO₃^--N in the total nitrogen and soluble oxalate content of the spinach shoots,and in Treatment 25:75 in NH₄⁺-N/NO₃^--N ratio,the soluble oxalate content was the lowest.Obviously,proper partial replacement of NO₃^--N by NH₄⁺-N is beneficial to decreasing contents of nitrate,nitrite and oxalate in spinach. (3) Proper partial replacement of NO₃^--N by NH₄⁺-N increased Vc content in spinach shoots,and it was the highest in Treatment 50:50 in NH₄⁺-N/NO₃^--N ratio.Content of soluble sugar in spinach shoots gradually decreased with the NH₄⁺-N/NO₃^--N ratio,and content of crude protein was the highest in Treatment 25:75 in NH₄⁺-N/NO₃^--N ratio.