Abstract: The infrasound generated from certain equipment has great physical and psychological influence on operating personnel. Through a detailed acoustic measurement and systematical data analysis, and by taking into account physical and psychological characteristics of the infrasound, an infrasound field improvement method is proposed. The proposed method is based on analyzing the theoretical defects of the "common position resonance method" which also leads to great discrepancy between experimental and actual states. The comparative experiments of insulation sound are carried out in different conditions, such as with and without sound absorption inside sound insulation cabin, float mounting of test cabinet, with and without sound absorption inside test cabinet. Testing parameters include sound level and acceleration. Experimental results show that the proposed sound insulation method achieves a 15~20dB noise reduction in frequency band from 20 to 40Hz, which meets well with the anticipated.