In recent decades, the amount of reactive nitrogen (N) has rapidly increased. While the reactive N, mainly chemical N fertilizers, meet food and economic development demands, it has also caused many environmental problems. Now, there are the triple challenges of food security, environmental degradation and climate change for the world due to the rapid increase of reactive N. Most of reactive N has been input to soil firstly, which would export to hydrosphere, atmosphere, and biosphere after transformed as different N forms through various N transformation processes. Thus, soil N transformations play very important role in regulating the fate of soil N. In this article, we review the methods determining the rates of soil N transformations, and clarify the role of soil gross N transformations to regulating soil N dynamics and its mechanisms. Our results suggest that the coupling of soil N transformation with climate and plant species-specific N preferences play important role in optimize N use efficiencies in agricultural production. However, scientists usually just qualitatively discuss the feedbacks and its mechanisms between plants and soil N transformations, due to the limitation of research methods. The quantitative investigation on the effects of these feedbacks on soil gross N transformations is of important significances to understand the feedback and its mechanisms between plants and soil N transformations, to optimize N fertilization, and to make N pollution control countermeasures and so on.