Auxetics are innovative engineered mechanical metamaterials that exhibit negative Poisson’s ratio, which will contract/expand transversely under axial compression/tension. The interest of developing auxetics arises as producing auxeticity has been reported to provide enhancements in various properties, such as impact and indentation resistance, energy absorption capability, fracture toughness, and strain sensing, etc. In this study, we propose a new auxetic composite system consisting of auxetic pyrolytic carbon lattice as reinforcements, along with two different matrix materials (epoxy polymer and foaming silicone). Although studies have reported the outstanding properties of the pyrolytic carbon lattices, harnessing the structural benefits from auxetic architectures to further enhance the properties and integrating the pyrolytic carbon lattices into different matrix materials have not been investigated. In this paper, we present our results on the failure mechanism and the compressive properties of the proposed lattice structure reinforced composites. The results for the pyrolyzed lattice samples showed that the compressive strength tend to decrease as the sample sizes increase. For silicone foam reinforced samples, the compressive strengths reached one time higher than those of the lattice samples. Samples with epoxy resin as matrix showed a consistent compressive modulus of around 1.2 GPa for all sample sizes. The compressive strengths were found to be increasing as the sample sizes increase. DIC results showed that the epoxy resin reinforced samples no longer possess the auxetic behaviors. X-ray μCT results showed that the debonding between the lattices and the epoxy resin matrix initiated prior to any other damage types.