The Northeast Region is one of concentrical distribution area of peat lands in China.In this region there are rich peat reserves constructed by various plant residues.Those residues have become basis of peat classification and utilization. The paper introduced the concept of plant residue,its signification and study way,and then proposed a classification system for plant residue.In additions9 the authors also made preliminary approach to types,characteristics, component and micro-structure of plant residue in peat in the Northeast Region.