The invention discloses a secondary aluminium battery, including a positive electrode, a sulfur-containing negative electrode and non-aqueous electrolyte, wherein an active material of the positive electrode is a sulfur-containing polymer. The secondary aluminium battery prepared by the above active material of the positive electrode has a main chain and a benzene ring for conduction and a side chain for energy storage, and good charging cycle performance and charge-discharge specific capacity. And a preparation method is simple and is environmental without pollution.