In existing metrology information system, the original record is not compiled in the online process, and the certificates cannot be generated automatically. Thus the work efficiency of calibration link is not high, and the certificate error rate cannot be reduced. This paper puts forward the method on how to realize online original records compilation and certificates automatic generation. It describes the difficulties in the process of design and matters needing attention in the information system. And it analyzes the advantages of the improved system and how to avoid the potential risks to the laboratory operation.