Abstract: Nitrogen (N) has a dual function in the ecological environment.On the one hand, nitrogen is an essential element for plant growth and development in agricultural production, and supplement of nitrogen fertilizer is required when soil N can't meet the crop demand.On the other hand, too much application of nitrogen in fertilizer and waste will pollute the environment.Ammonium nitrogen in environment will be oxidized into nitrate nitrogen, which will be N₂O formation resource, causing severe environmental problems.This article mainly introduced the influence of N₂O emissions from biological processes and biological processes.At the same time, the main factors influencing soil NO₃^--N leaching were summarized.Research avenues for some aspects of the N₂O emissions and NO₃^--N leaching study were also discussed.