The subject of the application presented in the drawing is a method of machining a cylindrical gear of any contour with longitudinal modification of the tooth line on a numerically controlled machine tool. The method consists in mounting the gear housing in a holder on a numerically controlled machine tool in five axes X+Y+Z+A+C, where the origin of the workpiece coordinate system (X, Y, Z) is located at any point geometrically related to the axis of rotation of the gear, then the cylindrical milling cutter with a spherical tip, as a result of the combination of movements Xn, Yn, moving in the area of the tooth gap, removes the allowance in one plane defined in the direction of the Z axis and the tool moves with a working movement, removing the material concurrently between points P2-P5 and P3-P4, increasing the distance between the points accordingly until the entire allowance is removed in the machining plane, and during machining, a finishing allowance is left in the form of an equidistant line forming the tooth line and the tooth profile, and the machining of shaping the tooth profile consists in lowering the machining plane in the direction of the Z axis by the ΔZ value appropriate to the type of roughing or finishing machining and the size of the tooth gap, wherein the combination of movements Xn, Yn in roughing is carried out in such a way that the tool moves in a working motion, removing material in the machining plane between the sides of the tooth slots being machined, and during machining, a finishing allowance is left in the form of an equidistant line forming the tooth line and the tooth profile, and machining is carried out by lowering the machining plane in the Z axis direction by the value ΔZ, while the combination of Xn, Yn movements in finishing is carried out in such a way that the tool moves in the machining plane between the tooth flanks, removing only the allowance left in the form of an equidistant line on the tooth flanks, and machining is carried out by lowering the machining plane in the Z axis direction by the value ΔZ, and furthermore, the tooth line is formed in such a way that the tool (2), as a result of the combination of Xn, Yn movements, moving in the area of the intertooth slot, removes the allowance in one plane defined in the Z axis direction, and the tool moves in a working motion, removing material concurrently between points P2-P5 and P3-P4, increasing the distance between the points accordingly until the entire allowance in the plane is removed machining, while shaping the tooth profile involves lowering the machining plane in the Z axis direction by the ΔZ value.