<p>To investigate the microevolution and the mechanical damage patterns of dolomite under water environmental effects, a study was conducted on the micro-scale mechanisms and the degradation mechanisms of dolomite under the dolomite formation in the Central Yunnan Water Diversion Project in Yunnan Province. This research explored the response mechanisms of micro-pore structures under the combined influence of water and pressure, further delving into the energy evolution patterns and failure mechanisms of dolomite under water absorption. Experimental results indicate a positive correlation between the T₂ spectrum and the mass increment of samples with increasing confining pressure. By establishing mathematical expressions relating water saturation, mass increment, and peak strength, the evolution curve of peak strength with water absorption time was obtained. Analysis of the variations in the percentage of water molecules in the microstructure under the combined influence of water and pressure revealed the differing rates at which water molecules enter pores of various sizes. Simulated diagrams of water absorption networks were constructed based on the water absorption characteristics of micro-crack, meso-crack, and macro-crack. Utilizing energy formulas, the energy dissipation patterns during dolomite failure were analyzed. By examining the ratio of energy consumption difference to strain difference, denoted as <InlineEquation ID="IEq1"> <EquationSource Format="TEX">\(K_{k}^{u}\)</EquationSource> <EquationSource Format="MATHML"><math> <msubsup> <mi>K</mi> <mrow> <mi>k</mi> </mrow> <mi>u</mi> </msubsup> </math></EquationSource> </InlineEquation>, a strain–energy dissipation ratio slope variation graph under the combined influence of water and pressure was constructed.</p>