These days, a quiet motor is in great demand. The primary source of noise of low speed motor and small motor is electromagnetic factοrs. In this paper, electromagnetic vibration and acoustic noise of the motor were numerically simulated through study of fluxes, mechanical natural frequency of stator, mechanical deformation of stator and so on. Flux distribution was calculated by electromagnetic FEM. Natural frequency ,deformation of stator and vibration were calculated by mechanical structural FEM. In natural frequency analysis, contact between stator core and frame was experimented and spring elements were introduced at contact point. Acoustic noise from the motor was calculated by BEM program. Calculated and experimental noise level were within about 3 dB(A).