Take Moya statue area of Shifosi cite in Chongqing as the engineering background, this paper proposes a research method for determination of the physicochemical properties of stone relics that cannot be moved through field survey as well as the application of cross-scale analysis method in immovable stone cultural relics. Laboratory tests were conducted by macro and micro tests, and the former include triaxial tests and direct shear tests, which were used to measure the basic mechanical parameters of samples. The micro tests include scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Through SEM, it can be seen that the sample is standard sandstone of large porosity, indicating that it is highly sensitive to water. In the long-term dry-wet cycle, its strength will decrease with time, namely, the typical water-rock interaction; XRD experiments show that the high content of clay minerals in sandstone leads to poor hydrologic properties and weak weathering resistance, which is also the main reason for weathering. Geological radar survey and auxiliary acoustic detection show that this method can be used to carry out macroscopic and microscopic cross-scale scientific analysis of cultural relics under the premise of effective protection of cultural relics.