Occurrence of secondary resonance in a dynamic damper device of a lock-up device is inhibited to improve effectiveness of the dynamic damper device. The lock-up device includes a drive plate, a driven plate coupled to a turbine, an intermediate member, a plurality of outer peripheral side and inner peripheral side torsion springs, and a dynamic damper device. The intermediate member is disposed between the outer peripheral side torsion springs and the inner peripheral side torsion springs. The outer peripheral side torsion springs elastically couple the drive plate and the intermediate member in a rotational direction. The inner peripheral side torsion springs elastically couple the intermediate member and the driven plate in the rotational direction. The dynamic damper device includes an inertia ring coupled to the intermediate member.