The invention discloses a preparation method of N-doped carbon hollow sphere electrocatalyst with the inner layer carbon inlaid with the metal nanoparticles. Firstly, a hydrothermal method is utilizedto prepare metal metallic oxide particles covered with an oxygen containing carbon layer; then, polydopamine is deposited on the outer surface of the oxygen containing carbon layer; and high temperature pyrolysis is conducted, polydopamine is pyrolyzed to form a carbon-nitrogen compound, and combined into the structure of the oxygen containing carbon layer to form the N-doped carbon-nitrogen compound layer. Nickel-cobalt oxide in the innermost layer is partially reduced by carbon generated through high temperature pyrolysis, metal elementary substance nickel and cobalt are formed, and embedded into the structure of the carbon-nitrogen compound from inside to outside, accordingly a hollow cavity structure is formed in the inner layer, and thus the carbon hollow sphere with the outer layercovered with the carbon-nitrogen compound and the inner layer carbon inlaid with the metal nanoparticles. The material has a highly stable electrocatalytic activity on an oxygen reduction reaction, can be recycled repeatedly, and has the important application in the field of zinc-air batteries by serving as a cathode material.