An opening cylinder for an open-end spinning device has a core piece over which the opening cylinder is fastened on a drive shaft and a tooth-set carrier supporting the tooth-set. The tooth set-carrier is fastened to the core piece by a clip connection in the axial direction. Additionally, the opening cylinder has a device for the form-fitting connection of the core piece and tooth-set carrier in the circumferential direction with a projecting part and a corresponding recess. The tooth-set carrier is fastened with a clip connection to a core piece of the opening cylinder in the axial direction. The tooth-set carrier has a projecting part for the form-fitting connection with the core piece in circumferential direction.