XML(eXtensible Markup Language) based electronic catalog is very useful for searching target information because of its structural and contents based searching support capability. And XML document editing is easier than HTML because of XML document is divided by structure, contents and presentation. This paper is to present a prototype of XML based Electronic Catalog Management System(ECMS) whose system consists of data input, output and manipulation system for inserting, updating, editing and deletion. A proposed system could resolved the problems at virtual intermediary shopping mall invloved in the difficulty of interoperability when customer try to compare similar products at mixed shopping mall and reduced web service costs at independent shopping mall by using XML format. The proposed ECMS offers rapid response capability for product data change of electronic catalog and easy and friendly interoperability among similar products.