Carbon Fiber Reinforced Polymer (CFRP) sheets have been widely used in strengthening different concrete elements such as beams, slabs, and columns. This sparked the interest of many researchers to conduct research on CFRP sheets; to have a better understanding for their behavior. This paper studied numerically the effect of using CFRP as a strengthening technique for Reinforced Concrete (RC) beams subjected to blast loading. A previous experimental investigation done by a Chinese researchers was considered in this study as a reference, and was modeled numerically (using ABAQUS) for this study. The model was then calibrated in order to conduct the numerical analysis on the effect of CFRP. Three different configurations of CFRP were considered: bottom CFRP strips for flexural strengthening, diagonal side strips for shear strengthening, and U-shaped strips for both shear and flexural strengthening. The variables considered in this study were; the mid-span deflection, strain in steel reinforcement and structural damage in both beams and CFRP sheets. Results showed that using CFRP in the bottom tensile face of RC beams helps in absorbing blast energy. In addition, using CFRP has shown a reduction in the tensile strain of the beam reinforcements.