The mechanical and thermophysical properties of quaternary-layered carbides, Zr-2[Al(Si)](4)C-5 and Zr-3[Al(Si)](4)C-6 have been investigated and compared with those of Zr2Al3C4 and Zr3Al3C5. These four carbides are generally alike in mechanical and thermophysical properties due to their similar crystal structures that consisting of alternatively stacked ZrC layers and Al3C2/[Al(Si)](4)C-3 slabs. The layer thickness of zirconium carbide and aluminum carbide has effects on their properties. Thicker layer of zirconium carbide and/or thinner layer of aluminum carbides are in favor of stiffness, hardness, thermal, and electrical conductivities, but go against density, specific stiffness, Debye temperature, and coefficient of thermal expansion.