In a commutator motor, a brush holding device includes a plurality of brush holders and a substantially annular holder plate. Each of the brush holders includes a holder frame, which receives a pair of brush and spring, and a bottom plate having two opposite side portions. The holder plate is disposed around a commutator and has a major surface on which a plurality of pairs of guide walls are formed; each pair of the guide walls defines a pair of grooves. The side portions of the bottom plate of each of the brush holders are respectively fit in a corresponding pair of the grooves defined by the guide walls. Each of the brush holders has a radially outer end that abuts an inner surface of a side wall of an end frame, whereby radially outward movement of each of the brush holders is restricted by the end frame.