The invention relates to a device for turning up a tyre-building part on a tyre-building drum using a roller lever. In order to produce a device for turning up a tyre-building part on a tyre-building drum, by means of which the tyre-building part is turned up without defects, in particular an unintended crease formation in the lateral wall, according to the invention the roller lever (5) comprises a lifting roller (7) on the side thereof directed towards the drum axis (3) of the tyre-building drum (2), opposite which a ramp-shaped component (12) is arranged. As the tyre-building part (1) is turned up, the roller lever (5) is raised by means of the lifting roller (7) to a pre-position, wherein, as the roller lever (5) is lifted to the pre-position, the crimping roller (6) is spaced in such a way that the crimping roller (6) is substantially exclusively in contact with the tyre-building part (1) and the roller rolls along the tyre-building part (6).