Abstract: Based on the concentrated mass explicit dynamic finite element method, we analyzes the effects of different observation house structures on free-field ground motion by taking the observation room structures as the control factor. The analysis models were established by testing the structure types of masonry observation house, semi-underground observation room and glass fiber reinforced plastics cover observation room. Moreover, the fixed observational test was carried out at the strong motion station of the Beijing National Earth Observatory. Based on the test record processing and the numerical simulation, the influence of the observation house structure on ground motion was analyzed. The results show that the influence of the observation room structure on ground motion is objective. Due to the difference of natural vibration period and volume of the observation room structures, the influence frequency band and the influence degree of different observation room on ground motion are also different. Compared with other structures, the influence frequency band of the glass fiber reinforced plastic cover on ground motion is narrow and the influence degree is the least.