While on-line shopping is increasing, the "Consumer Protection Law in Electronic Commerce" obliges each internet shopping mall to provide its business information. Although most internet shopping malls provide their business information in the semi-structured format on the bottom of their homepages, the attributes and expression forms of business information are different each other. It makes consumers difficult to identify their business information and lowers public confidence. Hence this study proposes three approaches - HTML-based structure, XML-based structure, and XML data island-based structure - to structuralizing business information for correct expression. The experiment results showed that the business information extraction time by XML data island-based structure is independent of the size of the web document, while the time by HTML-based structure is dependent on the size. By comparing the business information extraction times, we show that XML data island-based structure is more efficient and effective than HTML-based structure.structure.