Many nations have become victims of terrorism at a grand scale. Bombs have exploded in and around buildings in many countries causing civilian causalities and structural damage. As a result, such events have generated considerable concern over the ability of countries to protect buildings and their occupants from the continued threat of bombings. The issue of the structural integrity of existing buildings is now a burning one. This paper gives a basic emphasis on the blast response of a structure subjected to large TNT explosive. In this research work a FEM model was developed by placing a blast target at a distance of 30m away from the structure. The impact of blast with varying heights of the structure is measured with respect to coordinate axes. In distinction to the above ‘PRO’ Reflected over pressure has also been estimated for a structure subjected to blast loads. As a safety measure, the optimum thickness of shear wall has been recommended