Abstract: Compared are the advantages and disadvantages of the main material identification technologies(i.e.,radio frequency technology,OCR technology and bar code technology). Elaborated are the R & D of an antomatic steel pipe bar code spray and identification system. With IPC,and PLC controllers and the information-identifying sensor, the system is capable of bar code spraying and identification for steel pipes,being a reliable technological way to realize automatic acquisition, binding summarization and storage of massive data information,which can reduce the operator’s workload and improve the operation accuracy. Application of the on line marking and automatic identification technology has solved the issue of weld pipe on line real-time tracking and process tracing.