Abstract: Steel pipe transmission automation is realized by the steel pipe transmission automatic control system via PROFIBUS-DP field bus,Siemens S7-300 as the core,and the proper integration of relevant detection devices, operating components and actuator components. Focused on in the assay are such aspects of the said control system as the hardware configuration, mechanisms of the communication between PLC and frequency-transformer, software design, and anti-interference measures for the system. Thanks to the employment of the PROFIBUS-DP field bus technology,maintenance cost of the operation line is reduced,while safety level and running reliability of the operation line are improved.