Abstract: The numerical investigation results of concrete masonry unit (CMU) walls reinforced with carbon fiber reinforced polymer (CFRP) subjected to small stand-off distance explosive charge are presented. The 1/2 scale CMU walls were constructed, and the blast experiments were conducted to validate the numerical models which was used to analyze the blast response of the CMU wall reinforced with CFRP by the LS-DYNA explicit finite element code. The failure mechanism of CMU walls reinforced with single CFRP layer and three CFRP layers were investigated. The numerical results indicated that the CMU wall failed due to the blast load deriving the CMU blocks adjacent to the charge to tear up the CFRP sheets and disperse towards the rear of the wall. The failure forms of the CFRP sheets were tensile ruptures due to insufficient transverse tensile strength. The tensile ruptures of CFRP sheets stretched from the center zone to adjacent zones along the horizontal and vertical directions. When the cohesion strength between the CFRP sheets was insufficient, the high strength of CFRP in fiber direction could not be mobilized efficiently.