The invention provides a preparation method of MoS2 micro-nanospheres with a hierarchical structure, and relates to the technical field of preparation of micro-nanostructured materials. The MoS2 micro-nanospheres with the hierarchical structure are prepared through a hydrothermal reaction, an S source and a Mo source are added to a PAM (polyacrylamide) aqueous solution at the room temperature andstirred uniformly, and a reaction precursor solution is obtained; the reaction precursor solution is transferred into a reaction kettle and subjected to the hydrothermal reaction, and the MoS2 micro-nanostructured material can be obtained. According to the preparation method, the MoS2 micro-nanospheres with the hierarchical structure are successfully prepared from thioacetamide or thiourea as theS source, sodium molybdate or ammonium molybdate as the Mo source and a PAM template control agent with a simple hydrothermal method. Shaping of the MoS2 particles is realized, and one new method is provided for preparation of the MoS2 material with the hierarchical structure. The preparation method is simple to operate and low in cost, and the yield of obtained products is high.