Abstract: With the rapid development of numerical control technology and wireless communication technology, both are widely used in various aspects of industrial production. Aiming at the state, statistics, diagnosis and other small data acquisition and transmission process in CNC machine tools, in order to solve the problems of transmission distance, signal strength and cost of existing wireless technology, NB-IoT technology supports mass connectivity, wide coverage, and low cost to apply to machine tool networking systems.The test results show that the system can transmit the collected data stably.NB-IoT based machine tool internet of things system design provides economic and efficient networking scheme for machine tools.