High weathered soils in arid and semi-arid area are characterized by low soil fertility and high erosion potential. This paper evaluated the influences of nano-carbon on nitrate nitrogen transport on the sloping land (15°) of the Chinese Loess Plateau. Simulated rainfall experiments were performed on a natural, fallow loessial slope in the Shenmu Erosion and Environment Research Station, Institute of Soil and Water Conservation, Chinese Academy of Sciences, which locates in the Liudaogou watershed, Shenmu County, Shaanxi Province. Five application rates (i.e., 0.0%, 0.1%, 0.5%, 0.7%, and 1.0%) of nano-carbon were selected under the simulated rainfall experiments (rainfall intensity of 90 mm/h, and rainfall duration of 40 min). A constant-intensity rainfall method was adopted under natural conditions. Field plots were established on the slope that had been fallow for 5 years. The rainfall simulator came from the independent design of Xi'an University of Technology. Under the 90 mm/h rainfall intensity, the simulated rainfall experiments were carried out for 10 times in the 5 different pretreated plots in order to analyze the nitrate nitrogen loss for all the treatments. The main results were as follows: The application of nano-carbon in soil could effectively reduce the runoff and sediment yield, and the cumulative runoff and accumulated sediment yield had negative correlation with the amount of carbon applied in the soil. The application of nano-carbon could also reduce the nitrate nitrogen content in runoff and sediment, and the amount of nitrate nitrogen loss in runoff and sediment decreaseed with the increase of nano-carbon content. Compared with the change of nitrate nitrogen in soil profile, the application of nano-carbon could reduce the loss of nitrate nitrogen in the surface layer and increase the nitrate nitrogen content at 10—15 cm soil layer. By analyzing the effective depth of transport by runoff, the EDR under the control was max. With the increase of the amount of nano-carbon content, the EDR of each treatment decreased in turn. The results provide a guide for controlling soil water and nutrient loss on the sloping land.