The disclosed color display method is for a system provided with an automatic programming unit (101) which has a color display function, and an NC unit (102) without a color display function. In this color display method, the relationships between display items and display colors each corresponding to items in the NC mode are prestored in a memory (105c) of a control unit (105). When a display request key on a control panel (104), corresponding to a given item, is pressed when in NC mode, the control unit (105) informs the NC unit (102) of the name of the item whose display is requested, and inputs to a color display device (106) data on the color corresponding to the item requested. The NC unit inputs to the color display device item data corresponding to that item name. The color display device displays the item data in the color specified by color data which is input thereto.