A field experiment was conducted with biennial American ginseng as materials, and five nitrogen application rates were set to study the effects of different nitrogen levels on the accumulation of saponins in American ginseng. The results showed that different nitrogen levels had a certain effect on the content of American ginseng saponins. The total amount of nine saponins in stems and leaves had the highest value when the nitrogen application ratewas 5 g/m²; the content of root saponins has the highest value when the nitrogen application rate was 10 g/m²; thecontent of saponin Re changes obviously, and the content increased by 17.19% ～ 21.84% compared with the control group at 10 g/m² nitrogen application. Therefore, the best nitrogen application rate was 10 g/m².