In This paper, an improved adaptive genetic algorithm is presented for the design optimization on Permanent magnet synchronous motor(PMSM), which can availably reduce the iterative time and simplify the magnetic circuit calculation during optimization designing. To obtain higher computation speed, C++ language is applied to develop both the basic electromagnetic calculation program and optimization algorithm based on the Microsoft Visual studio 2010 development tools. According to the developed program, the optimal solution of motor designing can be quickly and accurately gotten, thus shortening the development cycle and improving the optimization design efficiency. In addition, the finite element analysis (FEA)is used in the motor design scheme before and after the optimization with static and transient ways, and the optimization design validity is confirmed through the simulated results.