Abstract: Tensegrity metamaterials have garnered a widespread attention in the field of energy absorption due to their unique advantages, such as delocalized deformation and reusability. This study introduces an innovative prismatic tensegrity metamaterial, which demonstrates a synergistic effect of compression-torsion coupling and negative stiffness under compressive loading. By developing a geometric theoretical model, this study first proves the geometric invariance of the initial torsional angle of the prismatic tensegrity structure across different configurations. Through a combination of quasi-static compression experiments and finite element simulations, the study investigates the influence of parameters, such as the number of polygonal edges, aspect ratio, strut prestress, cable stiffness and the radius of the mid-cross section, on the compression-torsion behavior and on the energy absorption properties. The results show that: by adjusting the geometric parameters, the prismatic tensegrity metamaterial can achieve a maximum torsional angle of 32.6° and exhibit negative stiffness once the compressive force reaches its peak, further enhancing its shock absorption and energy dissipation performance. This study highlights the unique advantages of prismatic tensegrity metamaterials in energy absorption and in shock damping, showcasing their significant potential in dynamic engineering applications, such as spacecraft landing buffer mechanisms and vehicle collision protection systems.