An NC device includes an accumulation portion for accumulating a report-item corresponding to a report-requiring situation that occurs in a machine. A voice generator control section of the device operates a voice generator to generate a voice for announcing a report-item accumulated by an accumulation portion if a determination portion determines that a operator-in-range information has been generated or in response to a request produced by a request portion. Contrastingly, the voice generator control section does not permit the voice generator to generate the voice if the determination portion determines that the operator-in-range information has not been generated. In this manner, the voice generation is performed efficiently and the operator is reliably informed of the report item.