Chitosan/MMT, PVA/MMT and Ch/PVA/MMT composite films were prepared by a casting technique. Surface morphologies examined by SEM and AFM suggested that particles are relatively wel dispersed in the chitosan matrix. Contact angle measurements and surface free energy determinations reveal that chitosan films are more polar than PVA films. In the case of chitosan composites, the polar component of the surface free energy is significantly reduced compared with the pure polymers. This behavior reveals the rather hydrophobic nature of this surface. The thermal properties of binarycomposite films are similar to those of the chitosan film. How-ever, the thermal stability of the composite decreases after theaddition of PVA. The mechanical properties were much better for chitosan composites with montmorillonite than for the PVA/MMTand Ch/MMT/PVA. The main reason for the poor mechanical prop-erties in the composite films might be due to the decrease in the homogeneity of the composites after the addition of MMT or PVA,which are stronger than the repulsive interactions. On the otherhand, the improvement in the physical properties of ternary and two-component composites can result from crosslinking reactionsbetween polymer chains and molecular interactions between chi-tosan, MMT and PVA. Another important result of this study is the appropriate selection of solvent used for preparing dispersions of montmorillonite. The results described in this paper verify that the swelling of MMT by the polymer solution was more effective whenwater was used as the dispersion solvent.