The invention belongs to the field of electrochemistry, and discloses a graphene/sulfur composite material and a preparation method thereof, a battery positive electrode and a preparation method thereof, and a battery. The graphene/sulfur composite material comprises graphene and elemental sulfur at a mass ratio of (1-5):(5-9), moreover, the elemental sulfur is embedded into the microcellular structure of the graphene. According to the graphene/sulfur composite material provided by the invention, the elemental sulfur is embedded into the microcellular structure of the graphene, a graphene/elemental sulfur composite material is prepared, the microcellular structure of the graphene with high specific surface area can prevent loss of a discharging product of sulfur, so that the solubility is reduced; meanwhile, since the graphene has high conductivity and is fully contacted with the elemental sulfur, the conductivity of a sulfur electrode is improved.