This article takes the Xiamen Sea reef engineering as an example to research the structure response of underwater blasting vibration on 4-story masonry-concrete building. The blasting seismic wave has been field monitored and the data has been analyzed with some means such as wavelet analysis. As a result, the characteristic laws of different floors’ structure responses under the effect of blasting vibration load have been acquired. With the floor increasing, the particles vibration velocity amplification coefficient of the forth top roof relative to the ground is approximately 1.36 to 2.086. The duration period and the main vibrationa are reduced respectively by 14%-28% and by 38%-56%; each floor’s vibration energy mostly concentrates in 0-25Hz’s band. The first floor’s energy mainly concentrates on 0-60ms, mainly distributing in 1st and 2nd frequency band, with the maximum appearing in the 1st band. And the vibration signal energy peak amplification coefficient relative to the ground is approximately 1.783 to 3.866.