Abstrct: Waterborne epoxy resins have poor water resistance and mechanical properties as wood adhesives at elevated temperatures and humid conditions due to containing water-soluble molecules or molecular chains. The organic modified nano-montmorillonite was mixed with waterborne epoxy resin to improve the water-resistance and mechanical properties of waterborne epoxy resin adhesives. The effect of different additions of organic-montmorillonite (0%, 3%, 6%, 9%) on the properties of the adhesive was studied by comparing the method of emulsion coating of montmorillonite with the direct addition method. The properties of composite adhesives were characterized by measuring the shear strength of wood block shear-type assemblies bonded with new formulated adhesives in dry and wet. The thermal stability and structure of the composite adhesives were investigated by thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The results show that shear strength of wood joints increased in all states by adding montmorillonite. Inclusion of organic-montmorillonite improved the thermal stability of adhesives to different degrees depending on montmorillonite loading. In addition, compared with the method of directly adding nano-montmorillonite, the adhesive was prepared by emulsion-coated montmorillonite, the organic-montmorillonite was more uniformly distributed in the adhesive and has better mechanical properties. It indicates that the dispersion quality of organic -montmorillonite in composites is the main reason for the performance of composite adhesives.