After archaeological excavations, in which the stable environments of mural tombs are broken, a variety of diseases may occur because of microenvironmental changes. In order to explore the effect of microenvironmental changes, a long-term monitoring of air temperature and humidity, and soil temperature, water content and conductivity was carried out in a simulated mural tomb at Shaanxi Normal University. The results show that external environmental changes can influence the microenvironment inside the tomb. The higher the soil is from the tomb bottom, the more significantly are the temperature and humidity changes, and also the more easily crisp powder formation and other diseases can happen. In addition, ion chromatography, X-ray diffraction (XRD), anti-damping drilling and some other methods were used for qualitative and quantitative analysis of the soluble salts in soil. The results show that the anion and cation contents of soil are positively correlated with the soil depth. The salts precipitated on the soil surface mainly contain sodium sulfate and calcium sulfate, which can easily cause the disease of crisp powder formation due to the constant microenvironmental changes. Based on the systematic research on microenvironments of mural tombs conducted, we can propose effective regulations. We are looking forward to providing more scientific bases for site protection.