Abstract: To study the movement of nitrogen (N) and phosphorus (P) on a purple soil slope during rainstorm runoff, the rainfall runoff process of Lanlingxi watershed in Three Gorges Reservoir Area was monitored in 2019 using a slope plot. Two rainstorms, typical of long-term uniform rainfall (June 22) and short-term heavy rainfall (August 3), were selected to analyze the impact of rainstorm characteristics on surface flow, interflow and N and P loss with runoff. The results show that: (1) there were significant differences in runoff, runoff duration, peak flow and runoff rate between the two rainstorm events. The time of peak rainfall intensity had a decisive effect on the interflow generation time. (2) Under different rainstorm conditions, the concentration of N and P in surface flow and interflow were significantly different. This was mainly affected by rainfall and peak rainfall intensity. The concentrations of N and P in runoff were negatively correlated with rainfall in the same period, and positively correlated with runoff in the same period. (3) Total N (TN) was the main form of soil nutrient runoff loss, and there was a significant positive correlation between N and P loss and runoff loss. On June 22 and August 3, TN loss was 4.03 and 8.49 kg·hm^-2, respectively, in which the contribution rate of interflow was 88.59% and 85.51%, respectively. The total P (TP) loss was 0.11 and 0.33 kg·hm^-2, respectively, of which the loss in granular form accounted for 54.55% and 60.61%, respectively. The results show that short-duration heavy rainfall caused greater soil erosion and nutrient loss. This provides a reference for the prevention and control of agricultural non-point source pollution in the Three Gorges Reservoir Area.