This work studies the numerical and experimental bending deflection of 3-point test of the composite beam made of epoxy reinforced by glass fibers and carbon fibers at different volume fractions .The results show that the deflection decrease in nonlinear relationship with increase volume fraction for both glass fibers and carbon fibers .The maximum difference between the experimental results and the finite element results difference was (11 %) at load (=20 N) and fibers volume fraction (Vf= 10 %) for glass fibers reinforcement. Also the results indicated that the maximum deflection was (1.65mm) when reinforced by glass fibers at (Vf =10 %) and at load (= 20 N) experimentally, while the maximum value of deflection was (0.55mm) when reinforced at the same load and fibers volume fraction.