In the occupant protection device according to the present invention, a restraint body joined with a driving mechanism is located near a target area of a seated occupant while being surrounded by an interior decoration member. Upon predicting a collision of the vehicle, the driving mechanism is actuated to protrude the restraint body from an opening in the interior decoration member for restraining the movement of the target area upon collision by its side facing the occupant, and when the collision is avoided, the driving mechanism returns the protruded restraint body in the opening of the interior decoration member. The restraint body is provided in the vicinity of its outer periphery with a retaining hole, a clip to be inserted in and retained by the retaining hole, and a guide surface for guiding the clip into the retaining hole for helping the restraint body to return in the opening of the interior decoration member. By this guide mechanism including the retaining hole, the clip and the guide surface, the restraint body is able to return to the opening of the interior decoration member smoothly without deteriorating the appearance.