Smart firefighting clothing is in urgent need of rigorous fire resistance. Here, a novel 2D nanomaterial, silver nanoparticle@polydopamine@M(OH)(OCH3) (M=Co, Ni) (AgNP@PDA@M(OH)(OCH3)), was utilized to construct self-assembled nano-coated aramid fiber (NCANF). Through phase interface catalysis and high-temperature reduction, NCANF forms a distinctive “metal–carbon–air” honeycomb-like buffer that enables NCANF to withstand the butane flame (1300 °C) for at least 60 s, exceeding the performance of firefighting uniform (FU, Nomex) in service. In this process, the back temperature of NCANF decreased by more than 50% compared to FU, with a maximum difference of 236.1 °C. NCANF offers a rapid fire alarm response under 3 s with a maximum resistance change rate of 15%, and supports the graded indication using arithmetic amplifier circuit. NCANF maintained a maximum resistance change rate of approximately 63% during 50 repeated bends of the manipulator joint. Leveraging the relationship between the joint bending angle and resistance change rate, an “attitude code” system can be established as the initial parameter matrix of a neural network and can enable the recognition of the firefighters’ body language. NCANF well solves the problem of current smart firefighting clothing that lacks rigorous fireproofing and is promising to establish a linked rescue mode based on real-time on-site information collection.