The importance of Electronic Commerce and internet has been rapidly increasing. For the global information society in the $21^{st}$ century, government aims for the successful execution of the project for the construction of KII(Korea Information Infrastructure). However, the research on applications of KII is not enough to relate with Electronic Commerce and its impact. In this paper, we present a brief introduction to KII and its characteristics. Through the detailed analysis of application factors on KII, the relationship and inter-necessity between KII and Electronic Commerce are investigated. Also, This, work studies the aspects of law, security, and Informatization- mind for the guided directions of activating Electronic Commece on KII. Finally, the implementation strategy for Electronic Commerce is suggested.