Taking the rural small and micro wetlands in Poyang lake basin as the research object，this study obtained the concentration and distribution characteristics of ammonia nitrogen in the water by investigating several rural small and micro wetlands，then used two ecological risk assessment methods，quotient method and safety threshold method，to analyze the data of ammonia nitrogen. The results showed that the concentration of ammonia nitrogen in the rural small and micro wetland in the basin of Poyang lake was between 0.18-2.75 mg/L in summer，26.1% of which exceeded the class III standard of surface water. Jinxian county had the highest rate of ammonia nitrogen exceeding the standard，while whose rate was the lowest in Xingzi county. After sorting out and analyzing the data of ammonia nitrogen in summer，the quotient method evaluation results showed that the micro wetlands in Nanchang county had short-term ecological risks to aquatic organisms，and the comprehensive evaluation results of the safety threshold method showed that the micro wetlands in summer had high risks. The results can provide scientific basis for ecological risk management of rural small and micro wetlands and scientific support for the construction of new countryside.