[Objective] The research aimed to study the microbiological degradation ability for ammonia-nitrogen,providing the reference for solving the problem of ammonia-nitrogen pollution in urban sewage.[Method] The high effective microorganism was isolated from urban sewage sludge,then utilized the biomass to test the optimal conditions of growth and identify its species,finally studied the ability of degradation under the optimal conditions.[Result] A high effective microorganism named DX3 to degrade ammonia-nitr...