Abstract: Combustion characteristics of epoxy resin matrix of T300 carbon fiber/epoxy composite and T300 carbon fiber/epoxy composite-foam laminate(there are a layer of T300 carbon fiber/epoxy composite in the upper and lower parts and a layer of 4 mm thick H60 Divinycell foam core material in the middle part) were experimentally investigated under different fire conditions using cone calorimeter. The change law of the combustion characteristic parameters of the ignition time, heat release rate, total smoke release quantity and CO generation rate were analyzed. The morphology images of T300 carbon fiber/epoxy composite before and after combustion, and the carbon layer morphology image of epoxy resin matrix and T300 carbon fiber/epoxy composite after combustion were observed by SEM. The influence of carbon fiber on pyrolysis and combustion of carbon fiber/epoxy composite was analyzed. The results show that the mean ignition time is shortened, the peak and first 300 s average of heat release rate are increased, the peak time is in advanced, and the residual percentage after burning is decreased with the increase in radiation heat flux. The ignition time, heat release and peak time of heat release rates of T300 carbon fiber/epoxy composite are delayed because of the inhibiting effect of the carbon fiber on pyrolysis and combustion of epoxy resin matrix. The ignition time, peak time of heat release rates and CO release time of T300 carbon fiber/epoxy composite-foam laminate are in advanced due to the low ignite of the foam core material.There ware obvious stratification phenomenon on T300 epoxy resin/carbon fiber composite and T300 carbon fiber/epoxy composite-foam laminate after burning, which results in the mechanical properties lose and the overall structure being destroyed. Carbon fiber has the inhibition effects on the pyrolysis and combustion of composites and the inhibition of the droplet, splashing and a lot of smoke generation in the combustion process.