Abstract: Through the collection of historical data, research and analysis of the data of the Fuzhou river basin, the main pollution areas and sources of total nitrogen in the basin were identified. According to statistical results, the total nitrogen load generated in the Fuzhou River Basin in 2022 was 16202 tons. The pollution sources were ranked in descending order based on their total nitrogen load contributions as follows: livestock and poultry breeding, agricultural planting, sewage treatment plants, rural population and direct discharge enterprises. The streets with high total nitrogen load output included Taiyangsubdistrict, Zhaotun Township, Fuzhou Town, and Wawo Town. At the spatial scale, the proportion of pollutant emission was calculated according to different subdistricts and environmental units, in order to delineate the main pollution areas. This revealed the fundamental causes of total nitrogen pollution in the Fuzhou River Basin, and clarified the main object goals for total nitrogen control.