The purpose of this paper is to examine the scope of the application of Preliminary Draft Convention, which will be fixed as international uniform rules soon, in relation to the CISG. First, this Draft Convention will cover service contracts as well as sales contract of goods, but the license agreement will be excepted because it does not transfer the complete property. Second, this will cover the commercial contracts(sales or services) concluded by data message fully or partially. Third, this will be applied in international contract regardless of contracting states or non-contracting states. As it is very difficult to confirm the places of business of contracting parties in on-line contracts, the first criterion to confirm them is the indication by the party in each contract. This presumption may be supplemented, if they are not indicated in the contract, by the location of the equipment and technology supporting an information system used by a legal entity for the conclusion of a contract. It is essential to establish an international uniform rules as soon as possible in order to activate the international businesses with on-line basis. Thus this author hopes that this paper will contribute to the clear understanding to the scope of application of Preliminary Draft Convention for which the UNCITRAL is under working.