A method of preparing a carbon fiber-reinforced silicon carbide composite material, comprising the steps of A or B: Step A 1) mixing a polymer resin with a carbon nanotube forming catalyst; 2) impregnating a carbon fiber with the mixture of the polymer resin and the carbon nanotube forming catalyst and then curing the impregnated carbon fiber to prepare a carbon fiber-reinforced polymer composite material; 3) carbonizing the carbon fiber-reinforced polymer composite material to prepare a carbon nanotube-containing carbon fiber-reinforced carbon composite material; and 4) melting metal silicon and then infiltrating the molten metal silicon into the carbon nanotube-containing carbon fiber-reinforced carbon composite material Step B 1) impregnating a carbon fiber with a polymer resin to prepare a carbon fiber-reinforced polymer composite material; 2) carbonizing the carbon fiber-reinforced polymer composite material to prepare a carbon fiber-reinforced carbon composite material 3) dispersing a carbon nanotube forming catalyst in the carbon fiber-reinforced carbon composite material; 4) forming carbon nanotubes in the carbon fiber-reinforced carbon composite material using a gas phase reaction; and 5) melting metal silicon and then infiltrating the molten metal silicon into the carbon nanotube-containing carbon fiber-reinforced carbon composite material. Step A 1) mixing a polymer resin with a carbon nanotube forming catalyst; 2) impregnating a carbon fiber with the mixture of the polymer resin and the carbon nanotube forming catalyst and then curing the impregnated carbon fiber to prepare a carbon fiber-reinforced polymer composite material; 3) carbonizing the carbon fiber-reinforced polymer composite material to prepare a carbon nanotube-containing carbon fiber-reinforced carbon composite material; and 4) melting metal silicon and then infiltrating the molten metal silicon into the carbon nanotube-containing carbon fiber-reinforced carbon composite material 1) mixing a polymer resin with a carbon nanotube forming catalyst; 2) impregnating a carbon fiber with the mixture of the polymer resin and the carbon nanotube forming catalyst and then curing the impregnated carbon fiber to prepare a carbon fiber-reinforced polymer composite material; 3) carbonizing the carbon fiber-reinforced polymer composite material to prepare a carbon nanotube-containing carbon fiber-reinforced carbon composite material; and 4) melting metal silicon and then infiltrating the molten metal silicon into the carbon nanotube-containing carbon fiber-reinforced carbon composite material Step B 1) impregnating a carbon fiber with a polymer resin to prepare a carbon fiber-reinforced polymer composite material; 2) carbonizing the carbon fiber-reinforced polymer composite material to prepare a carbon fiber-reinforced carbon composite material 3) dispersing a carbon nanotube forming catalyst in the carbon fiber-reinforced carbon composite material; 4) forming carbon nanotubes in the carbon fiber-reinforced carbon composite material using a gas phase reaction; and 5) melting metal silicon and then infiltrating the molten metal silicon into the carbon nanotube-containing carbon fiber-reinforced carbon composite material. 1) impregnating a carbon fiber with a polymer resin to prepare a carbon fiber-reinforced polymer composite material; 2) carbonizing the carbon fiber-reinforced polymer composite material to prepare a carbon fiber-reinforced carbon composite material 3) dispersing a carbon nanotube forming catalyst in the carbon fiber-reinforced carbon composite material; 4) forming carbon nanotubes in the carbon fiber-reinforced carbon composite material using a gas phase reaction; and 5) melting metal silicon and then infiltrating the molten metal silicon into the carbon nanotube-containing carbon fiber-reinforced carbon composite material.