This paper performs parameter optimization of proportional-integral (PI) and repetitive controller (RC) with a new objective function by adding two degrees of freedom for a three-phase boost power factor correction (PFC) rectifier. The main objectives are to optimize the multiple control loop parameters for total harmonics distortion (THD) reduction and dynamic performance indices improvement, including overshoot, rise time, and zero steady-state error. The control parameters of the three-phase boost PFC rectifier are optimized through a standard genetic algorithm. After obtaining the optimal PI and RC parameters values, fast Fourier transform and dynamic response analysis were performed using MATLAB. Moreover, separate evaluation functions are used to validate the optimal results in terms of THD reduction and dynamic performance indices improvement. Furthermore, the results are compared with the existing objective functions to show the proposed objective function superiority. Simulation results demonstrated that our proposed objective function outperforms existing objective functions to achieve optimal PI and RC parameters value. Finally, simulation results are validated through experimental results. The experimental setup includes a 5kW three-phase PFC rectifier with DSP TMS320F28335 prototype hardware to verify controller parameter performance.