The aerodynamic optimization design of a propeller for unmanned aerial vehicles (UAVs) is a complex and critical process that directly affects the performance and flight efficiency of the UAVs. This paper aims to improve the UAVs’ performance and efficiency, ensuring their stability and safety under various flight conditions. With thrust and hover efficiency of its propellers as the two optimization objectives, the propeller blade chord length and twist angle distribution as design variables, and the absorbed power of the propeller used as a constraint, the strip theory combined with the second-generation Non-dominated Sorting Genetic Algorithm (NSGA-II) are used in this paper for design optimization of the propeller. Through aerodynamic optimization and propulsion performance analysis, the hover efficiency of the propeller is enhanced. Results show that the optimized propeller increases its thrust and hover efficiency by 2% and 3%, respectively, providing significant support for the widespread application and development of multi-rotor UAVs.