Free vibration of symmetrically laminated composite rectangular plates with various boundary conditions is analysed by an extended Kantorovich method, in which a separable function to the dynamic-system energy equation is applied in order to reduce the partial differential equations to ordinary differential equations in the direction of x, y coordinates with a constant coefficient. The beam function is used as an initial trial function in the iterative calculation, which is employed to evaluate the natural frequency and force the final solution needed to satisfy the boundary conditions. To verify the accuracy of the present method, the frequency parameters are evaluated in comparison with previous work on thesubject. A good agreement proves that the method can be used to evaluate the natural frequencies of unidirectional 0, unidirectional 90 and cross-ply symmetrically laminatedcomposite rectangular plates
