With object-oriented modeling language many programers had improved and suggested various software development methodology on object-oriented analysis and design from mid 70's to 80's. Especially, UML(Unified Modeling Language), which was certified as a standard by OMG(Object Management Group) in 1997, has been proved to be efficient in modeling large-scaled and complicated system. In this paper, through object-oriented analysis and design which is based on UML, I will design and implement an e-Commerce system in the N-tiers distributed environment of Supplier-Head Office-Agency.