[Objective] To address the challenges faced by drive motors for nuclear reactor control rods, including magnetic performance attenuation caused by the large air-gap structure, temperature rise limitation in high-temperature environments, and the complexity of multi-objective optimization, this paper proposes an optimization design method that balance efficiency and accuracy. This approach aims to enhance the output torque, operational stability, and thermal reliability of the motor. [Methods] Firstly, an electromagnetic design scheme was developed for the motor, determining the initial scheme of 24 slots and 4 poles pole-slot combination, radial "I" type rotor magnetic circuit and Recoma28 samarium-cobalt permanent magnet material. Secondly, seven key structural parameters were selected as optimization variables. Sample data were obtained based on maximum-minimum Latin hypercube sampling. Parameter sensitivity was analyzed using Pearson correlation coefficient, and a high-precision Kriging surrogate model was constructed to replace finite element simulation. Thirdly, the non-dominated sorting genetic algorithm II (NSGA-II) was employed to conduct multi-objective optimization targeting maximization of average torque and minimization of torque ripple. Finally, temperature field simulations were performed using Fluent software to validate the effectiveness of the designed cooling structure. [Results] After optimization, the average torque of the motor reached 17.074 N·m, which was 15.03% higher than the initial scheme, the torque ripple was reduced to 0.29%, with a decrease of 87.97%. The maximum temperature under rated working conditions was 117.8 ℃, and the temperature rise was 58 K, meeting the requirements of class F insulation and class B temperature rise limit. [Conclusion] The combination of Kriging surrogate model and NSGA-II effectively solves the problem of high computational complexity of multi-parameter optimization. On the premise of meeting structural and environmental constraints, the designed motor has significantly improved electromagnetic performance and thermal stability, which can provide reliable power support for the nuclear reactor control rod drive system.