<p>The performance of stone columns as ground improvement techniques is significantly influenced by the stratification and heterogeneity of the underlying soil. This study investigates the behavior of stone columns installed in a multilayered soil system, where each layer exhibits distinct geotechnical properties such as stiffness, strength, and permeability. A parametric analysis is conducted to assess how variations in these properties across layers affect the load transfer mechanism, settlement response, and stress distribution within the stone columns and surrounding soil. The influence of layer thickness, position, and contrast in soil stiffness on the efficiency of the stone columns is systematically examined. Results reveal that the effectiveness of the stone columns is highly dependent on the relative stiffness contrast between layers and their spatial arrangement. The findings provide critical insights for the design and analysis of stone columns in complex subsurface conditions, enabling more accurate prediction of their performance in practice. Settlement at ultimate load (e.g., 400 N) could be reduced by as much as 40–45% by optimizing both L/D ratio and internal friction angle.</p>