Abstract: In automotive industry，each equipment comes from different suppliers，it needs bar codes to distinguish the products. Towards the automatic printing of bar codes after testing of headlight product，the paper realizes the automation of testing process. This paper presents MCU for DAQ and labVIEV for upper computer softwave，to realize the automatic printing of bar codes tested，it can change the bar codes in upper computer for differen products. The system has automation function，and has good stability proved by field use.

Key words: virtual instrument, automatic print, data acquisition, LabVIEW