Superamphiphobic fabrics with multiple functionalities have great potentials in intelligent textiles field to extend their applications and satisfy the needs of current industry. Herein, we report a simple water-based method to prepare superamphiphobic fabric with excellent anti-fouling and flame-retardancy. The beta-FeOOH nanoparticles which in-situ grow from the fibers not only endow the hierarchical structures with both high robustness factor (A*) and spacing factor (D*), but also could capture the produced free radicals to lower the decomposition rate when the fabric is heated. The relationships among the apparent contact angle (theta*), A* and D* are simulated based on the parameters of prepared structures. We also design a series of experiments to ascertain the growth mechanism of urchin-like nanoparticles and the optimal reaction conditions. The as-prepared fabric could maintain its superamphiphobicity towards extreme conditions, such as strong acid/alkali/salt corrosion, continuous impact of common fluids and longtime high-rate washing. This prepared material exhibits huge potentials in applications of multifunctional advanced textiles.