The invention belongs to the technical field of graphene-metal composite material preparing, and provides a method for preparing a graphene-metal composite material based on pulse magnetic oscillation. According to the method, in the metal condensation process, a pulsed magnet field is adopted, graphite is constantly stretched and peeled into graphene, meanwhile, metal branch crystals are crushed through electromagnetic vibration force, the graphene makes face contact with metal on a grain layer, and the graphene-metal composite material with the fine grain and the evenly-scattered graphene is obtained. Compared with a traditional method, the graphene can be prepared through peeling, and the problem about dispersibility of the graphene is solved; and meanwhile, the prepared composite material has the smaller grain size, and the mechanical performance is more excellent.