Proforma Invoice is a type of very-often-seen document in international trade practices, which has complicated attributes and uses. This master's thesis reviewed and analyzed the contractual attribute of Proforma Invoice from views of Being(Is) and Ought To Be that is whether a Proforma Invoice Being(Is) a contract and whether it Ought To Be a contract. From present definitions of Proforma Invoice, we can conclude it that a Proforma Invoice could have three uses, i.e. used for purpose of evaluation of cargo total payment sum or total costs, used for purpose of applying for foreign exchange and import permission and used for purpose of creation and signing of contracts, while first two purposes are this document’s traditional uses. In Chinese Court judgements, we have several different answers to the question that whether a Proforma Invoice is a contract, but we may conclude them roughly into three points of view, i.e. “it is a contract”, “it is the evidence of a contract” and “it is not a contract”. In USA court judgements, the points of views are of same complexity but the contractual attribute of Proforma Invoice is respected sufficiently. And in China domestic Criterion Files, the word of Proforma Invoice is used for the second purpose that is for purpose of applying for foreign exchange and import permission. In some made international conventions, Proforma Invoice is used together with word of contract in coordinate positions. From the view of International Commercial Tradition and International Merchant Tradition Law and their nongovernmental attributes, this living law that is the use of Proforma Invoice as creation of contracts in international merchant society should be respected, because this is one actually-existed international commercial tradition. And this dissertation analyzed the contract attribute of Proforma Invoice from different views including the conditions that make it non-contractual. So called contractual attribute, means Proforma Invoice acts as Offer or Acceptance in the deal, and this contractual attribute should be respected sufficiently in China domestic judiciary practices.
Conclusion: in may small-sum transnational deals, proforma invoice is being used as the carrier document of signing of international cargo sales agreement, so, it could be a part of international cargo sales agreement.
[Key Words] proforma invoice, contractual attribute, international customs