The influence of the particle shape of Al-pigments on the high-temperature degradation behavior of the organic silicone coatings on Ti-6Al-4V alloy was investigated in the precent article. First a coating (0F), as the calibrator was prepared by using TiO₂-particles as the pigment and with a ratio of TiO₂ to organic silicone resin of 3:2 (mass fraction). Then other two silicone composite coatings (2S) and (2F) were prepared by replacing 1/3 of the TiO₂-particles in the (0F) coating by 1% (mass fraction) of spherical Al-powder and 1 mass fraction of flake Al-powder, respectively. Then the variation of the microstructure, fracture morphology, and mechanical properties of the three coatings on Ti-6Al-4V alloy were comparatively examined during the heat exposure testing at 500 ℃, in terms of the effect of the partially replacing TiO₂ particles with spherical Al-particles (2S) and flake Al-particles (2F) on the thermal resistance, mechanical properties, and failure behavior of the organic silicone composite coatings. The results showed that the incorporation of flake-Al particles (2F) could significantly enhance the toughness of coating by inducing multiple crack deflections (namely, 60.89 kJ/m³, 65% higher than 0F coating). At elevated temperatures, their bridging effect could effectively dissipate the thermal mismatch strain energy, suppress the formation of through-cracks, allowing the coating to maintain structural integrity even after 100 h of heat exposure. In contrast, 0F and 2S coatings exhibited severe spalling due to the accumulation of thermal stress and resin degradation. These findings reveal that, the incorporation of flake Al-powder could significantly enhance the toughness of organic silicone coatings at high temperatures through a synergistic toughening mechanism (crack path extension and bridging effects), therewith providing a novel strategy for designing high-performance and heat-resistant coatings through regulating the particle shape of pigments.