The invention provides a preparation method of a lithium-sulfur battery cathode material and a lithium-sulfur battery using the cathode material, belonging to the field of lithium-sulfur battery electrodes. The lithium sulfur battery comprises a positive electrode material, an electrolyte, a separator and a negative electrode material. In-situ hydrothermal synthesis was used to prepare cathode materials. A layer of sulfur was deposited on VS2 to obtain VS2/S composite, which was used in lithium sulfur batteries. The preparation steps of the composite material are simple and easy to operate, and the yield is high. Compared with the cathode material without VS2 addition, the electrochemical performance of the cathode material with VS2 addition in lithium sulfide batteries is better. VS2 hasgood conductivity and accelerates the reaction kinetics. Secondly, it can immobilize sulfur and inhibit the shuttle of polysulfide, which improves the cycle stability of lithium sulfide batteries.