A method and apparatus for creating numerical control data by entering coordinates which specify points on a drawing placed on a tablet. A minimum reading distance is preset at the time that coordinate values of points are to be entered from the tablet. This is followed by entering the coordinate values of prescribed points on the drawing by designating the points at random using a coordinate designating device. The coordinate values of the designated point are generated each time the coordinate designating device travels a distance equivalent to the minimum reading distance, or sampling pitch, as the device is moved continuously along a graphic appearing on the drawing. Then, numerical control data is created by using the generated coordinate values. Numerical control data approximating straight line segments can be readily created, even for curves other than straight lines and circular arcs, by setting the sampling pitch interval to a suitable value.