This study addresses various types of water seepage diseases affecting the Dazu Beishan Rock Carvings in Chongqing, proposing grading evaluation methods and criteria for these water-related diseases. Utilizing the cubic law of flow-equivalent opening, critical conditions for grading drip/flow water diseases under different hydraulic gradients were established. The content and film thickness of bound water in the purple-red and gray-white sandstones of Dazu were evaluated by means of thermo-gravimetric analysis, leading to the formulation of immersion disease grading based on immersed area. Hygroscopic dynamic characteristics of the sandstones were examined under varying relative humidity(RH) through hygroscopic testing, and water diffusion coefficients were calculated based on Fick’s law. Wall hanging water disease conditions were defined, and grading standards taking into account contact angle were proposed. Additionally, the CIE-L^*a^*b^* chromaticity coordinates of the sandstones from Dazu were measured in both dry and wet states, establishing wet/humid disease grading criteria based on the color difference value ΔE_n corresponding to different saturation levels(water content).