The invention discloses a preparation method of a nitrogen-doped porous carbon@cobalt-based catalyst nanocage composite material for a lithium-oxygen battery. The method comprises the steps of firstlyweighing 2-methylimidazole and a cobalt metal salt and dissolving into a solvent separately to obtain a 2-methylimidazole solution and a cobalt metal salt solution; dropwise adding the 2-methylimidazole solution into the cobalt metal salt solution, or dropwise adding the 2-methylimidazole solution and the cobalt metal salt solution into an ethanol solvent at the same rate, standing and incubating, centrifugally separating the obtained product, repeatedly washing the product by using ethanol and then drying to obtain a bulk MOF; putting the bulk MOF into a mixed solution of the cobalt metal salt and a zinc metal salt, reacting at 60-150 DEG C for 1-12h, centrifugally separating the obtained product, repeatedly washing the product by using ethanol and then drying to obtain a hollow MOF; carbonizing the prepared hollow MOF in an inert atmosphere; and finally activating powder obtained after carbonization in an air atmosphere to obtain the nitrogen-doped porous carbon@cobalt-based catalyst nanocage composite material for the lithium-oxygen battery.