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Finding effective cathode materials is currently one of the key barriers to the development of magnesium batteries, which offer enticing prospects of larger capacities alongside improved safety relative to Li-ion batteries. Here, we report the hydrothermal synthesis of several types of WS₂ nanostructures and their performance as magnesium battery cathodes. The morphology of WS₂ materials was controlled through the use of sodium oxalate as a complexing agent and different templating agents, including polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), and hexadecyltrimethyl ammonium bromide (CTAB). A high capacity of 142.7 mAh/g was achieved after 100 cycles at a high current density of 500 mA/g for cathodes based on a nanostructured flower-like WS₂. A solution consisting of magnesium (II) bis(trifluoromethanesulfonyl)imide (MgTFSI₂) and magnesium (II) chloride (MgCl₂) in dimethoxyethane (DME) was used as an effective electrolyte, which contributes to favorable Mg²⁺ mobility. Weaker ionic bonds and van der Waals forces of WS₂ compared with other transition metal oxides/sulfides lay the foundation for fast discharge/charge rate. The enhanced surface area of the nanostructured materials plays a key role in enhancing both the capacity and discharge/charge rate.