The reaction kinetics of a biphenyl epoxy/polyol system was characterized by an isoconversional mode under dynamic conditions using differential scanning calorimetry (DSC) measurements. The results showed that the curing of epoxy resins involves different reaction stages and the values of activation energy is dependent on the degree of conversion. At the initial stage of cure, the phenol hydroxyl-epoxy reaction is predominant, then the hydroxyl group generated during curing can catalyze the reaction. The results were supported by the isothermal experiments.