As we know that nowadays the increase in the number of terrorist attacks especially in the last few years has shown the effect of blast load on buildings is a serious matter that should be taken into consideration in the design process. Although these kinds of attacks are exceptional cases, man-made disasters; blast loads are in fact dynamic loads that need to be carefully calculated just like earthquakes and wind loads. In that I have calculated the blast load manually by using IS code 4991-1968 and the analysis is carried out in multi-storeyed building by using STADD-Pro Software.