Abstract: In order to determine the leaching characteristics of nitrogen and phosphorus in urban rainwater pipeline sediments, three different functional areas (education area, traffic area and commercial area) of rainwater pipeline in Nanjing Jiangbei new district were taken as the research object. The relationship of nitrogen and phosphorus in sediments with leaching time was investigated. The leaching characteristics for both nitrogen and phosphorus under different environmental factors such as pH and salinity were analyzed. The effect of nitrogen and phosphorus in the influent on the corresponding effluent was discussed. The results showed that: (1) The leaching rate of ρ(NH₃-N), ρ(NO₃-N), ρ(TP) in the sediments of the three functional areas increased first, and then stabilized with the increase of leaching time. The order to reach leaching equilibrium was in the order traffic area > education area > commercial area. (2) The influence of pH on both NH₃-N and TP in the sediments of the three functional areas was basically the same, with the leaching trend of acid condition > alkaline condition > neutral condition. The leaching rate of NO₃-N reached the peak at pH = 7 (neutral condition). The leaching rate (35.21%) in traffic area was the highest. (3) The leaching rates of NH₃-N and NO₃-N increased with the increase of salinity. The leaching rate of TP fluctuated to different degrees when the salinity was higher than 1%. (4) The influent had the most significant influence on the effluent in the traffic area with the lowest NO₃-N leaching rate and the largest TP leaching rate, and the correlation coefficients were all greater than 0.97. Overall, compared with education and commercial areas, environmental factors such as pH and salinity had the greatest impact on the release of nitrogen and phosphorus from rainwater pipeline sediments in traffic area, which should be seriously considered when quantitatively assessing nitrogen and phosphorus output load from rainwater pipeline.