Deep cement mixing (DCM) method is one of the effective methods widely used to significantly enhance the stability of soft soil and provide resilient foundations for various structures. For decades, the DCM method has been utilized and has proven effective in strengthening soft soil. The lack of ductility remains a concern in DCM. The integration of fiber reinforcement in DCM represents a promising solution for mitigating the seismic hazards associated with soft soil. The primary focus of this study is to investigate the impact of steel and PP/PE fibers on the compressive strength of soil–cement piles. This experimental study involves geotechnical characterization of soil and uniaxial compressive strength tests in assessing the impact of steel fiber and reinforced PP/PE fibers on the mechanical properties of cemented sandy soil. The results demonstrate the pivotal role of fibers in changing the soil cement fiber matrix’s brittle behavior to ductile, exhibiting post-peak behavior. Furthermore, the findings reveal a more significant improvement in the compressive strengths of soil cement matrix when PP/PE fibers are incorporated into the matrix, thereby contributing valuable insights to the application of ground improvement techniques for seismic hazard mitigation.