The main source of electromagnetic vibration are torque ripple, cogging torque and Magnetic Pull Force (MPF). However, the optimum design of torque ripple minimization actually doesn't have an effect on vibration. This paper carries out an investigation of electromagnetic vibration by using Finite Element Analysis (FEA). The validity of the proposed approach is confirmed by the results from the 2D FEA about relation of electromagnetic vibration and torque ripple. If the method is used, optimal design of low vibration and torque ripple is possible.