A force characteristics mathematical modeling of motion process and optimization method was proposed to handle the selective miniature circuit breaker (SMCB) performance issue. The proposed solution resolved the collaboration of force characteristics among the operation mechanism components, and improved the miniature circuit breaker control characteristics. Based on the operation mechanism principle, it established the mechanical model of closing, breaking and tripping process. The Adams simulation platform was set up to analyze the operating mechanism motion process force energy distribution. Besides, it built the mathematical model for the operation mechanism structural parameters, and analyzed the topology optimization design via the quantum particle swarm algorithm. The optimized handle operating force was 7.4 N, and the operation mechanism achieved the optimal operation performance on the basis of reliable closing of miniature circuit breaker. The optimized tripping force was 0.48 N, which minimized the friction between the extension plate upper end and the lock catch upper end and achieved the miniature circuit breaker quick release. Finally, it designed the 100 A SMCB experiment prototype. The experimental results showed that the proposed prototype achieved good control performance, and the operation mechanism force characteristics collaborated well with the electromagnetic mechanism motion threshold characteristics under short-circuit. Thus, it met the selective protection goal.