Surface modification of CNTs with SiO2 coating was proposed to fabricate Al matrix composite with high-content intragranular reinforcements. The deposition of SiO2 nanoparticles on the surface of CNTs improved their compatibility with the Al matrix and thus increased the penetration of CNT@SiO2 reinforcements into Al grain interiors during powder processing. The intragranular reaction during the sintering process converted the CNT@SiO2 hybrid reinforcements into Al4O4C nanoparticles, leading to a remarkable increment in reinforcement content. As a result, incorporating CNT@SiO2 reinforcements (0.5 wt% CNT coated with 2 wt% SiO2) into Al resulted in a final composite with 9 vol% nanoreinforcement, of which 85 % were located in the grain interiors. The high-content intragranular reinforcements greatly improved dislocation storage capability and strain hardening rate, resulting in a significant increase in strength while retaining good ductility. The composite's yield strength and tensile strength increased to 370 MPa and 472 MPa, respectively, which were about 66 % and 67 % higher than those of the CNT-Al composite with the same CNT content.