The invention discloses a method for preparing graphite by using hydraulic cavitation liquid-phase stripping. The method comprises the following steps of dispersing graphite into a solvent containinga surfactant, and fully stirring, so as to obtain a dispersion solution of graphite; enabling a pump to send the dispersion solution of graphite into a cavitation element at flow rate of 0.5 to 50000L/h, maintaining the cavitation pressure at 0.1 to 50MPa, and maintaining the system temperature at 4 to 50 DEG C in the cavitation process, so as to obtain a primary cavitated dispersion solution; continuing to send the primary cavitated dispersion solution into the cavitation element, and repeating the cavitation operation for 1 to 200 times, so as to obtain the dispersion solution after cyclic cavitation; collecting the dispersion solution after cyclic cavitation, centrifuging for 5 to 120min at the rotation speed of 500 to 1000rpm, obtaining a supernatant, and freeze-drying, so as to obtaina graphene powder. The method has the advantages that the technical equipment is supplied; the operation is simple, the stripping efficiency is high, the product quality is high, the energy consumption is low, the pollution to environment is avoided, the scale production is easy, and the application prospect is broad.