PLC is a featurerich, highly intelligent device. Taking microelectronics technology as the core, integrating automation technology, computer technology and communication technology and so on, it has been widely applied to industrial control now.The specific functions of PLC and its application in the industrial control field were described. The latest progress of current PLC and its supporting technologies were introduced. The future directions of PLC were summed up. In terms of the current application and future trends of PLC, PLC will make the industrial control more automation and intelligence.