Abstract: The isothermal cure behavior of epoxy-polyam ide and epoxy-polyam ide-glass m icroballsw ith varying composition w as investigated by the dynam ic torsional vibration method in four varioustemperatures. The gel time tg and apparent activation energy Ea of cure reaction w ere estimated. Theeffect of glass m icroball on gel time and apparent activation energy has been considered. The nonequilibrium thermodynam ic fluctuation theory can successfully describe and p redict the mechanicalproperties of the resin system w ith or w ithout glassm icroball during the curing p rocesses.