Described is a procedure for controlling the shape of a complex metal profile obtained by a successive series of a plurality of bends of a metal sheet on a panel bender machine equipped with a data processing and functions control unit for the machine comprising the entering in the processing unit of data relative to a drawing of the complex profile with physical coordinates, as well as data relative to the thickness of the metal sheet and the distance from the axis of the panel bender machine of the metal sheet-profile edge, and conversion of the drawing supplied with physical coordinates into a digital image with imaging coordinates. The nominal profile processed as above is shown on a suitable display superimposed on the image of the complex profile of the metal sheet acquired by a suitably positioned TV camera. A visual control the correspondence between the two superimposed profiles is then performed on the display. From this comparison it is possible to make corrections to the bending parameters of the panel bender machine.