Unlike the sale of manufactured goods, commodity trading has a long history and is dominated by a small number of traders, making it difficult for outsiders to commodity trade. One such unique practice in commodity trade is string sales. The string sales refer to a form in which two or more contracts are linked to one cargo and the transactions are made on substantially the same specification, quantity and condition except for the price. Current Incoterms 2010 is attempting to apply Incoterms to the sale of commodities. However, the sale of commodities is an area of English law and customs dominated by GAFTA and FOSFA rather than Incoterms. In addition, these association contracts explicitly exclude Incoterms and CISG. Under this kind of situations, this study examines that Incoterms can replace the English Law as a law for commodity trade and Incoterms can be a unified rule through verifying the structure and characteristics of string sales, which are a unique structure of commodities. Finally, this study suggested the reasons why Incoterms is difficult to replace the English law designed by the commodity trading and what needs to be supplemented to overcome the limitations for Incoterms.