The invention discloses an aluminum ash recycling process. The aluminum ash recycling process includes the steps that size mixing preprocessing is conducted on aluminum ash and water; then, processed aluminum ash slurry is added to a pressurization reaction kettle to be subjected to pressurization water leaching, leaching residues which have the chlorine content smaller than 0.01 and contain aluminum oxide or aluminum hydroxide and chlorine-salt-containing leachate are obtained through pressurization water leaching; and the chlorine-salt-containing leachate is evaporated, crystallized and concentrated to obtain a covering agent used for aluminum alloy casting or is defluorinated, evaporated, crystallized and concentrated to obtain industrial salt, and aluminum oxide is obtained by conducting high-temperature (400-1200 DEG C) sintering on the pressurization water leaching residue and can return to an electrolytic cell to serve as brown aluminum oxide raw materials. The preprocessing-pressurization water leaching process is high in comprehensive aluminum ash recycling rate, free of secondary water pollution, small in smoke pollution, high in water circulation use rate, friendly to the environment and beneficial to industrialized production.