Aiming at the problems of excessive nitrogen fertilizer input,limiting crop yield,low fertilizer use efficiency and serious air pollution in the crop production at the North China Plain,winter wheat and field trials were used to study the dynamic changes of N2O,CO_2and CH4fluxes,global warming potentials,wheat yield with nitrogen-reduction and synergists. The results showed that the N2O peak emission under nitrogen reduction with synergist appeared from sowing to tillering stage,and CO_2peak emission from flowering to grain-filling stage.The global warming potential of greenhouse gases in wheat fields was mainly determined by CO_2.Compared with the farmer's traditional nitrogen amount(FN),the N2O emission flux was reduced by 55.5%and 69.1%,respectively.The N2O emission peaks of nano carbon(NC)and dicyandiamide(DCD)were delayed by 1and 4days contrasted with FN and recommended nitrogen amount(RN).Compared with FN,total N2O and CO_2emissions from wheat fields with reduced N treatments were decreased by 21.5%~52.2% and 11.9%~ 33.6%,wheat production significantly enhanced by 6.2%~21.4%.In addition,compared to reduction 20%nitrogen based on RN (80%RN)under the nitrogen level of 180kg/hm~2,nitrogen- reduction with humic acid and Zn,NC,and DCD synergists increased winter wheat yield and net income,reduced CO_2and N2O total and flux emissions and decreased greenhouse gas global warming potential.The effect of nitrogen synergist DCD was better as s a recommended nitrogen efficiency mode in the wheat field of the North China Plain.