This study aimed to explore the characteristics of nitrogen loss in different growth periods of crops, which could provide theoretical basis for the prediction and effective control of nitrogen loss in dry sloping land of red soil. Under natural rainfall conditions, lysimeters were continuously used to collect the data about surface runoff, seepage water and nitrogen output process on dry slope of Quaternary red soil in northern Jiangxi. The results showed as follows:(1) Runoff generation of peanut land on dry slope of red soil mainly occurred at the flowering period with the most abundant rainfall. Leakage water was the main form of runoff in peanut growing period, accounting for 64% of the total runoff. (2) Leakage water was the main path of nitrogen loss in all growth periods, primarily in the form of soluble nitrogen, occupying 54% to 99% of total nitrogen (TN) loss. Nitrate nitrogen (38%~50% of TN) was the main component of nitrogen loss in seepage water during all periods except the ripening period of full fruit. (3) Nitrogen concentrations in surface runoff and seepage water in the seedling period and flowering period were larger than those in other growth periods, while the nitrogen loss in them was the largest in flowering period. Therefore, the key periods for controlling nitrogen loss in peanut land on dry slope of red soil were the seedling stage with the lowest vegetation coverage and the flowering stage with the most concentrated rainfall. Besides, the crucial way to reduce nitrogen loss in the land was controlling nitrogen leaching loss such as nitrate nitrogen.