The invention discloses a preparation method of a pine needle-shaped carbon nanotube/carbon fiber composite carbon material. The preparation method comprises the following steps: carrying out ultrasonic cleaning on carbon paper in isopropanol, drying, carrying out heat treatment, soaking in concentrated HNO3, rinsing, and drying; dissolving ferric nitrate and sucrose in a mixed solvent of acidic silica sol and ethanol, and stirring to obtain a metal iron catalyst precursor solution; and soaking the carbon paper into the solution, carrying out suction filtration, drying, placing on a porcelainboat, introducing Ar, heating to 280-290 DEG C, switching to H2, reducing, adjusting the flow of Ar and H2, heating to 745-755 DEG C, injecting a xylene ferrocene mixed solution into a reaction tube,reacting for 2-3 hours, closing H2, cooling the tubular furnace to 420-440 DEG C in an Ar atmosphere, calcining for 2.5-3.5 hours, and cooling to obtain the catalyst. According to the invention, multi-walled carbon nanotubes with high graphitization degree, high distribution density, large specific surface area and uniform tube diameter can be deposited on the pretreated carbon paper carbon fibers.