Abstract: The traceability systems are regarded by many countries in the world as an effective method for controlling farm product safety. The issues of data exchange between various nodes on supply chain and the center of traceability system were needed to address for traceability based on government supervisor mode. eXtensible Markup Language(XML), an advanced language standards for Internet, is capable of modeling any data structure and used as a main tool for information sharing on WWW. In this paper, based on analysis of data flow of supply chain, the data model of traceability on vegetable products was summarized. Aiming at fulfilling seamless exchange of data, an XML-based vegetable traceability markup language(VTML) was established and an XML-based schema for vegetable traceability(VTML schema) was designed. The application of data exchange of vegetable traceability based VTML was discussed. The result showed that the differences of heterogeneous databases were shielded by setting up data mapping between VTML document and data source. It is proved that the mode of data exchange based on VTML is an effective approach to achieving the traced data synchronization.