Method for automated surface processing of a profile component in the form of a profiled large component of a wind turbine, having a processing device having a movement portal, a robotic system having a control system and a processing tool of a working head having the steps of: - moving the movement portal as a carriage along a profile face of the profile component, - positioning the processing tool substantially transversely relative to the profile face of the profile component by means of a positioning robot which can be actuated between a carriage and the processing tool, - surface processing of the large component with the processing tool, wherein by means of the control system a travel movement of the movement portal and a positioning movement of the processing tool are carried out by means of the positioning robot in accordance with the provisions of a virtual model (MODELL) of the profile face of the profile component, wherein at least one contour (KONTUR) of the profile face is stored in the control system which is formed in accordance with a virtual model (MODELL) of the profile face of the profile component and the contour (KONTUR) is established by the control system and the processing tool is guided along the contour (KONTUR), - implementing a number of surface processing passes on the large component, characterised in that there is arranged a rotation device of a retention portal which is connected in terms of control to the processing device for rotatably retaining the profiled large component of a wind turbine, by means of which - the displacement of the movement portal is carried out as a carriage free from mechanical limitation along a profile face of the profile component; - in order to implement the number of surface processing passes on the large component, the contour (KONTUR) along which the processing tool is guided comprises a point grid with opposing reversal points (Ug1, Ug2, Uk1, Uk2) which are associated at the longitudinal side with the profile face for a processing pass of the processing tool, wherein - a wear of the processing tool is monitored between a first and a second processing pass. - moving the movement portal as a carriage along a profile face of the profile component, - positioning the processing tool substantially transversely relative to the profile face of the profile component by means of a positioning robot which can be actuated between a carriage and the processing tool, - surface processing of the large component with the processing tool, wherein by means of the control system a travel movement of the movement portal and a positioning movement of the processing tool are carried out by means of the positioning robot in accordance with the provisions of a virtual model (MODELL) of the profile face of the profile component, wherein at least one contour (KONTUR) of the profile face is stored in the control system which is formed in accordance with a virtual model (MODELL) of the profile face of the profile component and the contour (KONTUR) is established by the control system and the processing tool is guided along the contour (KONTUR), - implementing a number of surface processing passes on the large component, - the displacement of the movement portal is carried out as a carriage free from mechanical limitation along a profile face of the profile component; - in order to implement the number of surface processing passes on the large component, the contour (KONTUR) along which the processing tool is guided comprises a point grid with opposing reversal points (Ug1, Ug2, Uk1, Uk2) which are associated at the longitudinal side with the profile face for a processing pass of the processing tool, wherein - a wear of the processing tool is monitored between a first and a second processing pass.