Epoxy composites based on low-viscosity cycloaliphatic oligomer ST-3000 and amine hardener Jeffamine T-403 filled with cerium dioxide with a concentration of 1–5 wt.% were synthesized. Thin film coatings were obtained on the surface of aluminum alloy D16, and their protective properties were studied. Alloy plates with applied composite coatings were subjected to electrochemical corrosion and climatic tests. The effect of CeO2 on the thermophysical properties of composites, resistance to high-temperature oxidation and thermo-oxidative destruction, as well as anticorrosive properties were studied. It was found that the introduction of cerium dioxide into composites does not prevent the formation of a homogeneous polymer structure, which is confirmed by the values of the glass transition temperature and the temperature of completion of the transition to the highly elastic state. Composites containing the inorganic filler are more resistant to thermo-oxidative destruction under isothermal and non-isothermal conditions. With a coating thickness of 10 μm, epoxy-inorganic coatings have an anti-corrosion protection efficiency of 98 %. It was established that the anti-corrosion properties of the obtained coatings depend on the method of preliminary preparation of the metal substrate. The compositions of composite coatings resistant to a humid air environment and variable temperature was determined.