CeO₂?modified three?dimensional nitrogen? and phosphorus?doped carbon?based catalysts (CeO₂?NPC) were prepared with cerium chloride hexahydrate as the precursor,sodium chloride as the template,and milk as the carbon source.The results of rotating disc electrode (RDE) and rotating ring?disc electrode (RRDE) tests were used to analyze the influence of catalyst preparation conditions on the oxygen reduction reaction (ORR) process.The influence of the synthesis process on the structure was investigated by X?ray photoelectron spectroscopy (XPS) and Raman spectroscopy.Heteroelements such as N and P spilled out with small molecules during calcination temperature increase.In this process,the degree of defects on the carbon carriers was increasing and the content of CeO₂ was invariably in an increasing trend.