Abstract: Nitrogen is a principle nutrient for agricultural production, however during agricultural activities and consumption process, the low use efficiency and high loss rate of nitrogen have subsequently led to a series of nitrogen pollution problems. To improve the understanding of nitrogen use efficiency and its characteristics on environmental loads during agricultural production could help to develop approaches reducing the nitrogen release intensity. The present study established a nitrogen flow model of agroecosystem to analyze the nitrogen flow characteristics in Chishui Township, Nancheng Township and Shangyong Township, allocated in Dehua County in Daiyun Mountain Area of Fujian Province, using material flow analysis method. Results show that from 2002 to 2016, the nitrogen flow flux of crop production system in these three townships declined, especially the nitrogen input in Chishui Township decreased from 86.40 kg·hm^-2 in 2002 to 37.19 kg·hm^-2 in 2016. However, the nitrogen inputs in all these three townships were still higher than the national average level, and the excessive input of fertilizer nitrogen which accounted for 45.56%-72.26% of the total nitrogen input in crop production ecosystem, is the main reason of environmental nitrogen load in this area. Furthermore, in Shangyong Township, the nitrogen utilization rate was 27.05%-35.05% and the nitrogen loss rate was lower than that of the other two townships. Though the excessive fertilization has been progressively controlled during the last two decades, the relatively low nitrogen use efficiency and high loss rate compared with the national average level are still major problems for crop production in this area. It is therefore essential to develop sustainable agricultural production system in local farms for optimizing the environmental benefit. It is recommended to adjust the fertilizer formulas, improve the utilization rate of agricultural wastes and increase the recycling rate of nitrogen, to comprehensively reduce waste of resources and environmental pollution.