The invention provides an endogenous submicron TiB2 particle-reinforced aluminum-based composite material and a preparation process, the composition: Zn 4.5-10wt%, Mg 1.0-3.0wt%, Cu 1.0-5.0wt%, Zr 0.05-0.25wt%, TiB2 Particles 5-20wt%. Process: After the industrial pure aluminum ingot is completely melted, cover the aluminum melt with a covering agent and raise the temperature; after the aluminum melt is kept warm, add the dried Al-Ti master alloy, KBF4 or NaBF4 reaction salt, and stir; after the reaction, Remove reaction salt slag, add industrial pure Zn, Mg, Al-Cu, Al-Zr master alloy, refining and degassing treatment, remove scum, pour into mold after standing; billet homogenization treatment, wagon, and then hot extrusion Pressing or rolling processing; the composite material after extrusion or rolling is subjected to solution aging treatment, and quenched in water at room temperature to obtain an ultra-high-strength aluminum-based composite material. The endogenous submicron TiB2 particles are fine, the surface is clean, and the utilization rate of the reinforcement phase is high; the process is simple and suitable for large-scale production.