This paper dealt with changes of organic nitrogen forms during dairy manure composting with inoculating microbes.The results showed total nitrogen and acid hydrolyzing nitrogen obviously decreased during composting,and were lower in the treatment with microbe inoculation than in that without inoculation at different periods of composting,but there were no obvious differences at the end of composting.Amino acid nitrogen increased at the primary period,then decreased.At the end of composting,it increased significantly compared with that of the treatment without inoculation.Amide nitrogen and amino sugar nitrogen increased at the periods of temperature rising and high temperature,and decreased as temperature declined,then were constant at mature period.But at the different periods of composting,amide nitrogen and amino sugar nitrogen were obviously different among the different treatment.Amide nitrogen in the treatment with inoculation was obviously increased compared with of the treatment without inoculation,while the reverse was true for amino sugar nitrogen.