Water oxidation catalysts (WOCs) are essential to electrochemical hydrogen production, but (electro)­chemical instability remains a critical issue for WOCs especially under acidic conditions. Here we present a hybrid organic–inorganic polymeric dual network gel (DN gel) electrocatalyst based on earth-abundant elements via in situ oxidative polymerization of polypyrrole and simultaneous cyano-polymerization for efficient acidic water oxidation. X-ray absorption and X-ray photoelectron spectra reveal a synergistic interplay between the inorganic polymer and the organic conductive polymer in producing a favorable local coordination environment, further supported by the DFT calculation. The DN gel electrocatalyst exhibits highly active and stable catalytic activity for oxygen evolution in the pH = 0 electrolyte, with no noticeable degradation after more than 3000 cycles. This work presents an alternative insight into developing highly active and robust WOCs as promising alternatives to noble metal catalysts in strong acids.