Abstract: In this study, we propose a self-adaptive method for optimizing the main circuit parameters of the buck-boost matrix converter (BBMC) with its rated current to optimize the design of the main circuit parameters of the BBMC under different rated output currents. We study the optimal design method of the BBMC main circuit parameters based on the self-adaptive wolf group optimization algorithm by establishing a mathematical model between the BBMC optimization target and the optimized object; further, we study the variation law between the BBMC optimized design parameters and its rated output current to lay the foundation for obtaining the optimal design of the BBMC main circuit under different current quotas. Finally, we verify the theoretical analysis by a simulation.