Abstract: A piezoelectric-mechanical coupled high order model of composite plates with embedded piezoelectric patcheswas presented. The third-order laminate theory was used to describe the displacement field and a high order electric potential field was assumed to accurately describe the nonuniform distribution of an electric field through the thickness of piezoelectric patches. The simplified constitutive equations of piezoelectric material were presented upon the plane-stress stateassumption , and then the finite element formulas were deduced based on this high order model. The performance of themodel and the formula developed were validated by application in calculating the deformation of a bimorph beam and incontrolling the deflection of a square composite plate with piezoelectric actuators.