The invention discloses a method for separating a positive electrode material and an aluminum foil of a waste lithium battery by adopting red mud. The method realizes the separation of the positive electrode material and the aluminum foil in a positive pole piece of the waste lithium battery by adopting the red mud to serve as a high-temperature reaction medium, and the red mud serving as an in-situ reaction reagent promotes the high-temperature thermal decomposition of an organic binding agent polyvinylidene fluoride in the positive pole piece of the waste lithium battery and the absorption of a fluoride generated by the decomposition. Compared with the prior art, the method of separating the positive electrode material and the aluminum foil of the waste lithium battery by using the red mud to serve as the reaction medium can consume the industrial solid waste and convert the industrial solid waste into a fluxing agent for the separation of the positive pole piece of the waste lithium-ion battery on the one hand so as to solve the problem of industrial solid waste stacking, and also can realize the reduction, recycling and harmlessness of the industrial solid waste. The strippingrate of the red mud for the aluminum foil and the positive electrode material of the positive pole piece of the waste lithium battery can reach up to 97.0wt%.