Abstract: The reaction characteristics of nine kinds of epoxy resins cured with six kinds of curing agents are investigated by using Differential Scanning Calo-rimetry(DSC).The influence of the structures of epoxy resins and curing agents on reactions of different curing systems is discussed.By combining Charruogra-vimetry with DSC, the decomposition temperatures of cured products of mphenyldiamine/epoxy resins and 4,4'-diaminodiphenylsulfone/epoxy resins are studied.