Rising nitrous oxide(N₂O)concentrations in the atmosphere have exacerbated global warming. Forest soil plays a vital role in regulating atmospheric N₂O concentration. The effect of nitrogen(N)input on the N₂O fluxes of forest soil has attracted much attention. However, the response mechanism of forest soil N₂O emissions to N input, especially the regulatory effects of plants and microorganisms on N₂O flux, has not been systematically studied. Therefore, this article reviews how N input affects forest soil N₂O emissions through forest vegetation(root N absorption, litter decomposition, and formation of arbuscular mycorrhizal)and soil microorganisms(microbial biomass and community composition). The results show that the competitive N uptake of plants can reduce the promotion of N input on N₂O emissions. Importantly, the magnitude of its effect may mainly depend on the state of the soil "N saturation". Plant litter mainly affects N₂O emissions of forest soil under the background of N input through nutrient return and the release of secondary metabolites during the decomposition process. The former has a promoting effect and the latter has an inhibitory effect. The arbuscular mycorrhiza mainly regulates forest soil N₂O fluxes by absorbing available N and water, promoting the formation of aggregates, and changing the N₂O-related functional gene community. Nitrogen input leads to soil acidification or nutrient limitation, which can reduce microbial biomass and/or influence the composition of microbial communities, and then affects N₂O emissions. Nitrogen input also affects different production pathways of N₂O, which is regulated by soil moisture, the concentration of N₂O substrates, and the abundance of functional genes associated with soil N₂O emissions(AOB、 AOA、nirK、nirS and nosZ). In the future model predictions, plant N absorption, litter decomposition, mycorrhiza and N₂O production pathways can be fully incorporated into the model to improve the accuracy of model predictions, and provide a scientific basis for formulating forest management policies and greenhouse gas abatement measures under the background of global change.