Supplier selection knowledge of OTAs businesses is one of the most valuable and significant knowledge since OTAs now operate businesses that gain their benefits from having many kinds of tourism products and services for customers to browse from in their own online booking systems. The better the suppliers, the more successful will OTAs be. The knowledge in supplier selection is, therefore, relayed through manuals, mentoring and coaching. After that there has been a creation of knowledge management systems to be used as a media to pass on the knowledge via online means. The knowledge contents presented are retention and transfer knowledge. To evaluate the efficiency of using Knowledge Management System (KMS), the research has provided a study in increased learning performances of related staff in supplier selection who have learned through the KMS system. The result found that the group that learned through KMS gained higher learning performances than the one who learned from documents. This reflects that the KMS system will suitable to be used as a tool in knowledge management and can be relayed to organizations in this present time.