In this study, the deflection response of cantilever laminated composite square plates subjected to the weight of itself was analyzed using finite element and Taguchi methods. The plates with 12 plies were made of glass fiber reinforced polymer composites (GFRP). The arrangements and fiber orientation angles of the plies were conducted using Taguchi's L9 (33) orthogonal array. Each four plies was assumed to be control factor. Fiber orientation angles were varied from 10 to 90 in degree. Plates were modelled using finite element software ANSYS Parametric Design Language. Analysis of signal-to-noise (S/N) ratio was used in order to evaluate the control factors with the optimum levels for minimum deflection response. Analysis of variance was carried out in order to analyze the powerful influential control factors and their percent contributions on responses.