Abstract: Combined with a Tunnel Engineering in Linyi City,the spectrum changing situation of vibration signal at different distances from explosive source was analyzed through the analysis software MATLAB. It can be obtained that,in the medium and near-field of blasting source,the vertical component of the dominant frequency of vibration signal is larger than that in horizontal direction and the main vibration direction of ground vibration's peak velocity may change from horizontal direction to vertical direction with the increase of the distance from explosive source,and the overall trend decreases with vibration dominant frequency tending to low frequency. In engineering blasting site similar to this engineering in blasting parameters and features of the blasting region,the energy proportion of the horizontal component of vibration signal with low frequency is higher than that of the vertical component,and the impact of blasting vibration on building structures also can not be neglected even at the position far from the blasting source;in particular,seismic fortification in horizontal direction should be enhanced.