A finite element model was developed to trace the Static response of advanced composite thin walled beams made of Glass Fiber Reinforced Plastics (GFRP). The model is a four node rectangular layered element with six degrees of freedom per node. The element stiffness matrix for the model includes the effect of coupling between membrane and bending actions. The developed model has the capability of taking an arbitrary number of layers of different material properties for the analysis of sections. To demonstrate the accuracy and convergence of the program, the results were compared with those obtained by others in the literature. Stable convergence and good accuracy were obtained. The effects of material anisotropy, fiber orientation, fiber volume fraction and coupling between membrane and bending actions on the deflection of thin-walled GFRP composite beams were evaluated.