To evaluate soil nitrogen levels and their distributions and changes under the intensive crop production in fluvo-aquic soils in China during the late two decades, a comprehensive survey was conducted in seven typical fluvo-aquic soil regions in Huanghuaihai plain. The results showed the accumulation of soil nitrogen, soil total nitrogen content increased by 0－56.54% in most of fluvo-aquic soil regions, and soil hydraulic nitrogen increased by 2.03%－81.52% in all of fluvo-aquic soil survey sites. However, soil nitrogen generally was at lower level according to the grade criteria of soil nutrient, above 92% and 90% of the fluvo-aquic soil areas were under 1 g/kg for total nitrogen and 30－90 mg/kg for hydraulic nitrogen respectively.