In this study; deflection at the mid-point of laminated composite rectangular plate subjected to uniformly distributed load is investigated by finite difference method. Four edges of these plates are Navier SS-1 simplysupported. Classical theory of laminated composite plates formed by extending the classical plate theory is used. Differential equations about bending of plate were discreted by finite difference method and unknown displacements at the related nodes are calculated. As an example; mid point dimensionless deflections of specially orhotropic, regular symmetric and regular antisymmetric composite laminated square plates under uniformly distributed load were examined