In a torsional damper, a damper mass is connected to a hub through a damper rubber. The hub is provided with a boss fixed to a crankshaft and a rim holding the damper rubber. The boss and the rim are coupled by plurality of spokes. The plurality of spokes each has an inclined shape inclined in the axial direction. Reinforcement portion is provided in the spokes in one direction corresponding to a bending vibration to be input among the plurality of spokes.