The invention provides a preparation method of a silicon carbon composite material, and relates to the field of new energy batteries. The preparation method of the silicon carbon composite material comprises the following steps of: S1) firstly adding a silane coupling agent to nano silicon dispersion solution for reaction, adding graphene oxide to carry out reaction, finally adding a dispersing agent, and uniformly mixing the components to obtain dispersion solution of graphene oxide-coated nano silicon; S2) under a shearing and stirring state, spraying the dispersion solution of the grapheneoxide-coated nano silicon into the mixed powder of graphite and asphalt I for shear granulation so as to obtain precursor particles, wherein the graphite, the asphalt I and the nano silicon have a mass ratio of 1: (0.03-0.1): (0.05 to 0.2); and S3) drying and sintering the precursor particles obtained in the step S2) to ensure that the graphene oxide in the precursor particles are reduced to graphene, so as to obtain the silicon carbon composite material.