This paper introduces a new web technique-COM (an acronym for Component Object Model) for improving CLAIN web site and an instance of COM application to web design of CLAIN. COM is a way of building objects,that is independent of any programming language. COM as a core facilitates CLAIN development platform,which would obey the rule of CLAIN and extend functions with reusability. A data access component is designed in VC++. ASP.VB and VC application can call its function at the same time. And the role of COM in constructing CLAIN is discussed.