The invention relates to a method of cutting a sheet-like piece into one or several smaller pieces by using camera means and a controllable cutting apparatus, the directions and values of the coordinate systems of which are calibrated to correspond to each other. In the method the following measures are taken: the piece to be cut is placed on a cutting surface located within the recording area of the camera means, the piece is photographed by the camera means and on the basis thereof the outlines of the piece are determined and the information on the outlines of the piece is input into the positioning system, where the cutting paths are established and input into the control system of the cutting device, which determines necessary parameters for the cutting and on the basis of these, controls the cutting of the piece into parts according to given instructions.