The invention relates to a preparation method of a lithium sulphur battery composite anode material. The preparation method is as follows: preparing a mixed solution of carbon tetrachloride, a nitrogen source and carbonate, heating and flowing back to obtain a nitrogen-rich polymerization / carbonic acid salt compound; high temperature pyrolyzing in a nitrogen or argon atmosphere after drying the compound, so as to form the nitrogen-rich carbon / oxide compound; adding dilute acid to remove vestigial oxide, so as to form the nitrogen-rich multimode beehive carbon material of a multilevel porthole structure; uniformly mixing the nitrogen-rich multimode beehive carbon and sublimed sulfur, heat preserving under vacuum condition, injecting sulfur gas to the nitrogen-rich multimode beehive carbon material, so that the lithium sulphur battery composite positive material can be obtained. The composite anode material provided by the invention is alveolate, and has the advantages that portholes are abundant, sulfur content is high, sulfur particle can be distributed uniformly in the nitrogen-rich multimode beehive carbon material of the multilevel porthole structure, and the carbon sulfur particles can be combined more tightly, the material mechanical stability is high, discharge specific capacity is high, cycle performance is excellent, and technological process is simple, pollution is avoided, cost is low, and the method is liable to large scale production and application.