Aimed at the problems existing in the traditional control method, this paper presents a kind of μ fixed-structure controller design method based on penalty function particle swarm optimization algorithm. A classical fixed-structure controller, PID controller, which satisfies the μ index, is designed taking the DC drive model as the object and based on penalty function particle swarm optimization algorithm, compared with H∞-PID controller through the instance. The results indicate that the μ-PID controller has superiority over H∞-PID one in both standard and robust performance. Keywords: μ-PID; robust; DC drive; particle swarm optimization; constrained