The blasting theory and engineering practice proved that the strength andattenuation of blasting seismic wave vary from strong to weak and from quick to slow re- spectively,in accordance with from close to far away from the blasting centre. As viewedfrom this variation regularity,the combined value of calcuiation factors K and a related tovibration velocity can not be used,as usually,for calculating the blasting vibration velocitygenerally. The calculation of vibration velocity,therefore,should be conducted by selectingvalued K and a conformable to the real situation from the locations at different distancesaway from the blasting centre , then some relative consolidation measures are taken forbuildings at different locations to avoid a unnecessary loss or waste.