As factories and enterprises, many of the old grinder, and its work has been well below the needs of modern production. So it is necessary to the old conventional motor control system for technological transformation, PLC PLC to replace the conventional relays, so reducing the intermediate relay, the lines are simplified and improved reliability, to achieve the purpose of automatic control Grinder . First of all the old papers on the electrical system Cylindrical Grinder a brief presentation, pointed out the shortcomings of its existence, then made a better rehabilitation programmes. The programme will improve the control system hardware design and software design on two aspects. Some of these hardware design details of the PLC Selection PLC, I / O PLC and the schedule of the external wiring diagram of the painting, and software design of the PLC programming from the start with the general steps, then made the PLC program Design ideas and programmes, part of the process of analysis and mapping of the ladder. After the transformation of the grinder work safety and reliability, the system is running well, higher precision grinding the use of PLC control grinding machine running, and the grinder start, stop, failure to stop, emergency stop function, and a set of two-way control and automatic control Control methods, such flexibility will be under the operational requirements of the control switch grinder to achieve a grinder running automatic control. During the GZ066 Cylindrical Grinder of the PLC, making this the old idle equipment to play the original features and transformation of the new features, enhance the value of the machine. Finally, the technology can also be applied to other auxiliary equipment or other areas of control in automation. Key words: PLC PLC of Cylindrical Grinder