An armature in which a commutator and a lead-out section are firmly joined and satisfactory insulation is secured between an armature core and an armature coil. An armature (11) is equipped with: a shaft (2); an armature core (3) secured to the shaft (2); an armature coil (4) composed of conductors (4b) wound in slots (3a) formed in the armature core (3); a commutator (5) secured to the shaft (2); a belt-shaped member (13) which is provided to surround a lead-out section (4a) and which fastens a welded portion (A) where segments (8) of the commutator (5) and the lead-out section (4a) are ultrasonically welded; and a molded portion (12) which covers the outer peripheral surface of the armature core (3) and the outer peripheral surface of the lead-out section (4a).