The invention relates to a preparation method of a nanotube array positive electrode material of a lithium sulphur battery, which belongs to a preparation method of positive electrode materials of lithium sulphur batteries and solves the problems, such as poor electrical conductivity and low specific capacity, of an existing positive electrode material of a lithium sulphur battery. The preparation method comprises the following steps: (1) preparing a titanium dioxide nanotube array, (2) depositing a conductive reinforcing material, and (3) depositing elemental sulphur, wherein the steps (2) and (3) can be repeated to form a multiple depositional cycle period, so that a positive electrode material with a multilayer coaxial heterostructure is obtained, and has different sulphur loading capacities. According to the preparation method, the titanium dioxide nanotube array is taken as a substrate material, and the conductive reinforcing material and the elemental sulphur are compounded and deposited and enter titanium dioxide nanotubes to form the positive electrode material with the coaxial heterostructure, so that the conductivity of the positive electrode material is improved, the sulphur loading capacity of the positive electrode material is improved, the cycling performance and specific capacity of a lithium sulphur battery are further improved, and the preparation method has certain impelling action for speeding up the further large scale application process of the sulphated lithium battery.