In this study two deflection functions due to both the flexure and the shear of an orthotropic simply supported beam loaded linearly are obtained by means of the anisotropic elasticity theory. In order to see the effect of shear, the deflections are calculated for different fiber directions. Two different composite materials are used during the deflection analysis. The error level and the shear deflection for the thermoplastic composite beam are the smallest for 45 degrees orientation angle, and that for the polymer-matrix composite beam are the smallest for 90 degrees orientation angle. When the cross-sectional height to the beam-length ratio increases, the shear effect also increases.