In order to facilitate the assembly of the brush assembly and to improve the productivity, the brush device includes a positive side brush subassembly having a positive side brush for feeding a commutator, a positive side brush holder for holding the positive side brush, and a positive side plate to which the positive side brush holder is attached, and a negative side brush subassembly having a negative side brush for feeding the commutator, a negative side brush holder for holding the negative side brush, and a negative side plate to which the negative side brush holder is attached. The positive side brush subassembly and the negative side brush subassembly are combined with each other.