Abstract: A program for operating a numerical control machine tool written in problem oriented language is translated into machine oriented language through the use of the present NC tape producing system. The present system has a mini-computer mounted in a desk type cabinet, which has also a printer, an input tape reader, an output tape puncher, a key board, and a mini-board panel, each connected to said mini-computer. The mini-board panel is covered with the mini-board sheet indicating the roles of keys under the mini-board sheet. The system is automatically initialized just by turning on a power switch, or pushing a load key, and the program for operating the mini-computer itself is automatically loaded in the memory of the mini-computer through said input tape reader. Thus, the operation of the system is very easy.