The nearby reservoir water impounding causes the water level rise of Minjiang River where Leshan Giant Buddha locate at. It may affects the microclimate of the Buddha area, and the possible microclimate changes mainly include the temperature and rainfall, for the reason of protecting the long-term stability of the cultural relics, it is necessary to assess the rock weathering sensitivity of the Leshan Giant Buddha sandstone because of these changes. Via the indoor temperature cycling test, humidity cycling test and humiture cycling test, the stone samples’ elastic wave velocity and mass are determined in different condition of temperature and humidity. And the influence to the Buddha stone weathering caused by the changes of temperature and humidity is analyzed.