The work aims to design a set of alignment control system applied to packaging production line, for the purpose of simplifying control process and ensuring control precision and speed. First of all, the system structure was designed. Then, communication between hardware was set up. Finally, the database was established and the alignment program was written. Meanwhile, the system was tested and the operation process was illustrated through examples. The barcode information of the product on the production line could be read correctly by means of WINCC and SQL database at the speed of 50 products/min. Then the information was given back to PLC to perform operations accordingly. The system is of high reliability and convenient to maintain, operates simply and flexibly and has strong adaptability to different automatic production lines because of a less number of hardware and simple software structure.