The epoxy resin/curing agent/montmorillonite, nanucomposite was prepared by a casting and curing process. The intercalation and exfoliation behaviors of epoxy resin in the presence of organophilic montmorillonite, were investigated by X-ray diffraction (XRD) and dynamic mechanical thermal analysis (DMTA). For the diethylenetriamine curing agent, the intercalated nanocomposite was obtained; and the exfoliated nanocomposite would be formed for tung oil anhydride curing agent. The curing condition does not affect the resulting kind of composite, both intercalation or exfoliation. For intercalated nanocomposite, the glass transition temperature T-g measured by DMTA and affected by the curing temperature of matrix epoxy resin is corresponded to that of epoxy resin without a gallery. The alpha' peak of the loss tangent will disappear if adding montmorillonite into the composite. It was also found that the T-g of the exfoliated nanocomposite decreases with increasing mont morillonite loading.