Four new fertilizers (CRU:polymercoated controlled release urea,NU:urea containing nitrapyrin,DMPP:urea containing nitrification inhibitor 3,4dimethylpyrazole phosphate,EM:microbial inoculant combined application with urea) were selected as materials to study the effects of new fertilizers on photosynthetic characteristics and biomass and yield of double cropping rice in a field experiment.The four new fertilizers improved the net photosynthetic rate,CRU and DMPP got the best promotion in early rice and late rice respectively.Stomatal conductance was little influenced by nitrogen fertilizers,only CRU decreased it during early rice.Intercellular CO2 concentration and transpiration rate decreased significantly when CRU was used,and there were little differences between rice varieties among other fertilizers.Compared with the conventional urea,the new fertilizers all got remarkable biomass increment,and CRU achieved the most stable and highest yield increase by 19.9% (P<0.05) in both early and late rice，and NU,DMPP and EM achieved a yield increase by 14.6% (P<0.05) in late rice,no significant increase occurred in early rice．Better growth and yield promotion was showed in late rice than in early rice．