In this paper, a design of DC motor speed control system based on improved Beetle Antennae Search(BAS) is presented to solve the parameters setting problem of the double closed-loop DC motor speed regulator. Improved BAS and PID control is combined to constitute a BAS-PID controller with self-tuning function. In improved BAS, a “beetle” is substituted by multiple “beetles”, and the parameters to be optimized of the speed regulator are regarded as “beetles. In the given search space, the position of the beetle group is adjusted and updated by the fitness value of their best position. The optimal target is gradually approached through constant iteration. At the same time, the speed regulator based on improved BAS is compared with the traditional method. The simulation results show that the improved speed control system of DC motor has stronger robustness and faster response speed. And the superiority and feasibility of the improved speed regulator is verified.