A fastening device having a fastening element includes a plug-in region and a contact area at a distance therefrom, and a shaft between the plug-in region and the contact area. The plug-in region is axially pressable through a through opening in a wall area in a plugged position of the fastening element, until the contact surface, or an intermediate part situated in between, presses against the wall area from one side and the shaft is radially centered in the through opening. The fastening element is connected to another component. The fastening element is located in its installed position after the fastening element is in its plugged position through the through opening and is then rotated around an axis of its shaft into an installed position delimited by a stop, in which at least one radial projection of the plug-in region engages behind an edge area of the through opening to fix the fastening element in the installed position and thus prevent axial displacement of the shaft out of the through opening.