<p>This study explores how moisture content and confining pressure affect the damping ratio of silty clay, with a focus on their sensitivity under cyclic loading. A series of laboratory tests were conducted to establish the relationship between damping ratio (<i>λ</i>) and dynamic shear strain (<i>γ</i>_d) under varying moisture contents and confining pressures. The results show that moisture content has a strong influence on the damping behavior of silty clay. When the moisture content exceeds 12%, the rate at which the damping ratio increases with shear strain becomes significantly higher. This suggests that beyond this threshold, water begins to play a more dominant role in energy dissipation. Confining pressure also affects the damping ratio, but in a more gradual manner. Under low confining pressure, the damping ratio increases rapidly. However, as the pressure increases, the rate of growth slows, indicating that the soil structure becomes more resistant to deformation and energy dissipation. Overall, the damping ratio is more sensitive to changes in moisture content than to confining pressure—particularly during the early stages of loading. This highlights the importance of moisture as a controlling factor in the dynamic response of silty clay. These findings are particularly relevant for geotechnical applications in high water table or humid environments, where changes in moisture content can significantly impact soil behavior. The study provides valuable insight for the design and assessment of structures involving moisture-sensitive soils, emphasizing the need to account for variations in water content when evaluating damping characteristics.</p>