This paper describes the resonance characteristics of two types of commonly-used electric power steering motors: the 8-pole-12-slot and the 10-pole-12-slot motor. The relationship between the excitation modes and characteristic vibrational modes is clarified by conducting a coupled magnetic field-structural analysis and carrying out a modal analysis on a prototype. Finally, the 8-pole-12-slot and 10-pole-12-slot motors are compared in terms of their generated noise.