A robotic wheelhouse hemming apparatus includes a base. A multi-axis robot is mounted on the base. The robot includes an arm. A roller hemming head is mounted on an end of the arm for roller hemming. A slide mechanism is mounted for multi-directional movement on the base. A support is mounted on the slide mechanism. An anvil is supported on the support. A registration member is integral with the support and is engagable by the roller hemming head. The robot arm is operable to manipulate the roller hemming head into engagement with the registration member, and subsequent movement of the robot arm moves the support on the slide mechanism, thereby adjusting the position of the anvil relative to a workpiece to be hemmed.