Abstract:An 11-storey building with unsymmetrical construction had been demolished by directional blasting, and an idea blasting result had been achieved. The author analyzed the unfavourable effects of the unsymmetrical structure of building on its collapse, and proposed corresponding and effective precautionary measures. These give available reference for other similar blasting projects. The design of blasting parameters, pretreatment, blasting network and the safety measures were briefly discussed.