To explore the influence of the release agent on the fluidity of the aluminum alloy melt, continuous experiments were carried out. First, through a flat mold filling experiment, the aluminum alloy melt and temperature change of the flat mold were obtained via measurements under the condition in which the mold was coated with a powder mold release agent. Stable and minimal, the excellent thermal insulation performance of heat transfer coefficient. Then, fluidity measurement experiments and computer simulation were conducted to verify the influence of the density change of the powder mold release agent on the fluidity of the aluminum alloy melt during the casting process. It was found that this relationship was affected by the temperature difference between the mold and aluminum alloy melt. The experimental results showed that changes in the powder mold release agent density changed the distribution density of its components through the thickness of the coating, thereby affecting the fluidity and thermal insulation function.