The invention belongs to the technical field of sulfide nano-materials, and discloses a preparation method and an application of cobalt sulfide having a nano-lamella assembled three-dimensional annular micro-nano structure. The preparation method comprises the following steps: dissolving CoCl2.6H2O in ethylene diamine, adding thioacetamide, transferring the above obtained solution into a reaction kettle, and washing and drying the obtained product to obtain the cobalt sulfide having a nano-lamella assembled three-dimensional annular micro-nano structure. The method has the advantages of simplicity in operation, easiness in preparation, high controllability, cheap synthesis raw materials and high yield. The cobalt sulfide having a nano-lamella assembled three-dimensional annular micro-nano structure has good electrochemical performances. The initial discharge specific capacity of the cobalt sulfide is 745 mAh/g when the current density is 100 mA/g, and the capacity of the cobalt sulfide still reaches up to 392 mAh/g after 200 cycles when the current density is 1 A/g, so the cobalt sulfide has a good cycle stability, is a sodium ion battery negative electrode material having excellent performances, and has a wide application prospect in the energy storage field.