The invention discloses a method for recovering valuable metal from a waste lithium ion battery material, and belongs to the technical field of comprehensive recycling and resource recycling of electronic wastes. The method comprises steps of mixing the cathode material of the waste lithium ion battery with low-valence sulfate such as sulfur or sulfide; subjecting the mixture to a sulfuration calcination treatment at a temperature of 300 to 900 degrees centigrade; immersing a calcined product in water to obtain a lithium salt aqueous solution which can be further used for preparing a lithium carbonate product; subjecting to water leaching residues to oxidation acid leaching or direct acid leaching to extract valuable elements such as nickel, cobalt and manganese; and purifying and extracting the leaching solution to obtain the corresponding cobalt salt and nickel salt products. The method of the invention has a simple process and a short process flow. The sulfur dioxide gas generated by calcining the sulfide can be used for preparing sulfuric acid used for subsequent nickel-cobalt leaching, thereby achieving zero pollution discharge and finally achieving a purpose of comprehensively recovering the valuable metal in the lithium ion battery cathode material at high efficiency and low cost.