Two strains of T1, Z1 ammonibacterium were isolated from the biofilm of the BAF reactor. According to the morphologic observation and physiological biochemistry test, the strains T1, Z1 were preliminarily identified as Proteus and Micrococcus respectively. The research of the strains T1, Z1 for ammoniation characteristics indicated that the suitable temperature was 30°C, the suitable pH value was 7.0 and the best inoculum quantity was 5%. The strain T1 was strictly aerobic bacteria and Z1 was facultative aerobic bacteria. In these operating parameters, two strains of T1, Z1 were good of the degradation of organic nitrogen and the growth rate of ammonia nitrogen could respectively reach up to 86.91% and 69.98%. The strains T1, Z1 had a certainly practical value for treating the waste water with the high concentration of organic nitrogen.