The invention discloses a carbon nanotube reinforced copper-based composite material. The carbon nanotube reinforced copper-based composite material is prepared from, by weight, 0.5%-5% of surface-modified carbon nanotubes, 2%-5% of graphite, 6%-15% of Ti3SiC2, 2%-5% of boron nitride (BN), 0.01%-0.5% of rare earth element La and the balance copper. The surface-modified carbon nanotubes are carbon nanotubes of which the surfaces are grafted with gallic acid. According to the copper-based composite material, the surface-modified carbon nanotubes are used, the carbon nanotubes are good in dispersity, the bonding area with a copper matrix is large, the reinforcement effect is good, a better stress transfer effect can be achieved, stress concentration is reduced, and defects are reduced. In addition, the carbon nanotubes, graphite powder, Ti3SiC2 powder and BN powder exert the synergistic reinforcement effect in the copper matrix, the mechanical property and friction-resistant and wear-resistant properties of the copper-based composite material are significantly improved, and meanwhile the copper-based composite material has excellent strength and impact resistance. The invention further discloses a preparation method of the copper-based composite material. The method is simple in process, production is easy, and the method has a wide application prospect.