ABSTRACT Next‐generation wearable electronics and stealth technologies demand lightweight, flexible materials that integrate broadband electromagnetic absorption with thermal management. Conventional microwave absorbers often suffer from narrow bandwidth, high thickness, and composition‐driven limitations. Here, we introduce a bioinspired free‐space architecture engineering strategy that programs hierarchical pore–cavity configurations within graphene‐based fibrous textiles. Guided by cavity resonance theory, hollow fibers and aerogel fibers are fabricated via multi‐axis wet‐spinning and directional drying, enabling precise impedance modulation and synergistic conduction–polarization losses. The optimized architectures deliver exceptional performance: RAHF‐2 achieves an effective absorption bandwidth ( EAB ) of 8.6 GHz with the minimum reflection loss value ( RL min ) = −32.8 dB, while RMAF‐5‐E reaches RL min = −59.1 dB and EAB = 8.5 GHz, and RMAF‐10‐EA exhibits strong absorption (−42.0 dB) at an ultrathin thickness of 2.0 mm. Beyond electromagnetic protection, these textiles demonstrate rapid light‐to‐heat conversion (65°C in 60 s), offering multifunctionality for adaptive thermal regulation. This work establishes a structural design paradigm for next‐generation metamaterial textiles, bridging electromagnetic stealth, wearable protection, and intelligent thermal management.