Recently companies focus on traceability in the factory to control the risk to the products. It is an important task to collect many IDs marked on the items and sections to realize traceability; much equipment for IDs collection is required in the factory. This paper discusses the application to traceability of the information-connection unit of the programmable logic controller (PLC). This unit has a script engine, and the capability to communicate with information systems without a computer for enterprise application integration (EAI). Therefore, the data held by the PLC is integrated with such information systems as manufacturing execution system (MES), at less cost, less time, and easier. It is shown that this unit is also useful for traceability, which is regarded as one of its main functions