A motor assembly with coaxial shafts is provided which can be produced at low costs and in which a plurality of motors can be disposed with their respective rotary shafts arranged coaxially to one another with high coupling and assembling accuracy in a simple structure. Each motor includes a housing member and ball bearings to rotatably support the rotary shaft and two adjacent motors are fixedly coupled together such that the respective housing members of the adjacent motors are fitted with each other.