The method of pot culture was used to investigate the proper application rate of the nitrogen fertilizer during the period of under cadmium stress(50 mg/kg)plant growth.The study was carried out to examine the effects of different dosages nitrogen fertilizer［0,200,300 and 400 mg/kg CO(NH2)2］on photosynthesis and fluorescence characteristics of Zoysia japonica under cadmium stress.The results showed that different dosages nitrogen fertilizer enhanced chlorophyll contents,net photosynthetic rate,stomatal conduction,intercellular CO2 concentration,transpiration rate,photochemical quenching,maximum photo quantum yield,and the electron transfer rate and decreased nonphotochemical quenching(NPQ)under Cd stress,which demonstated that N fertilizer could release the effect of Cd stress on Zoysia japonica.For the effects of different nitrogen concentration on chlorophyll content of Zoysia(Chl a,Chl b,Chl a + b),stomatal conductance(Gs),intercellular carbon dioxide concentration(Ci),leaf maximum quantum yield of PSⅡ(Fv / Fm)and the electron transfer rate(ETR),it showed that treatment with 300 mg/kg nitrogen was the best,then 200 and 400 mg/kg.For the effects of different nitrogen concentration on net photosynthetic rate(Pn),transpiration rate(Tr),water use efficiency(WUE)and nonphotochemical quenching(NPQ),the result was that treatment with 300 mg/kg nitrogen was better than that of 400 and 200 mg/kg.However photochemical quenching(qP)was not significantly affected(P>005)by nitrogen concentration.It was concluded that 300 mg/kg nitrogen concentration had the greatest effect on Zoysia japonica under cadmium stress in this study.