This paper presents the development of highly stretchable conductive porous elastomers with low or negative Poisson's ratios through uniaxial, biaxial, and triaxial hot-pressing strategies. The materials, primarily composed of reduced graphene oxide (rGO) and polymer nanocomposites, exhibit exceptional stretchability, up to 1200% strain, and unique mechanical properties. The uniaxially hot-pressed elastomers show folded porous structures, while biaxially and triaxially hot-pressed elastomers exhibit reentrant porous structures, both of which contribute to high stretchability and negative Poisson's ratios. These materials are applied in ultrawide-range strain and pressure sensors, smart thermal management, and electromagnetic interference (EMI) shielding, demonstrating their versatility and potential in flexible electronics, thermal management, and energy storage. The work provides a versatile strategy for creating highly stretchable and negative-Poisson-ratio porous materials, opening new avenues for various applications.This paper presents the development of highly stretchable conductive porous elastomers with low or negative Poisson's ratios through uniaxial, biaxial, and triaxial hot-pressing strategies. The materials, primarily composed of reduced graphene oxide (rGO) and polymer nanocomposites, exhibit exceptional stretchability, up to 1200% strain, and unique mechanical properties. The uniaxially hot-pressed elastomers show folded porous structures, while biaxially and triaxially hot-pressed elastomers exhibit reentrant porous structures, both of which contribute to high stretchability and negative Poisson's ratios. These materials are applied in ultrawide-range strain and pressure sensors, smart thermal management, and electromagnetic interference (EMI) shielding, demonstrating their versatility and potential in flexible electronics, thermal management, and energy storage. The work provides a versatile strategy for creating highly stretchable and negative-Poisson-ratio porous materials, opening new avenues for various applications.