A shrink-fitting method for a laminated rotor includes: disposing, coaxially with a laminated rotor core, an annular ring having a through-hole, at an axial end of the laminated rotor core including laminated annular steel sheets and having a through-hole extending in its axial direction; and inserting a rotor shaft into the through-holes of the ring and the laminated rotor core after heating them. A ring attachment jig having a circular internal space, where the ring is disposed, has projections projecting from an axial end surface thereof in the axial direction and arranged along a circumferential direction of the circular internal space. The center of the ring is aligned with the center of the laminated rotor core, by fitting the projections in attachment holes axially extending in the laminated rotor core, and fitting the ring to an inner peripheral surface of the ring attachment jig, which defines the circular internal space.