The 1980 Vienna Convention on the International Sale of Goods, which was approved and implemented without the intention of interfering with the internal laws of countries due to integration based on the principle of freedom of contracts, by prescribing the possibility of waiving all or part of this protocol on business transactions; In the foundation of Iran's laws, especially in the discussion of purchase, it faces a conflict, which is the uncertainty of the price under Article 55. This conflict, which is one of the reasons for Iran's non-adherence to this protocol, has raised many questions at the world level, along with Article 14. The way of determining the contract price is different in the countries and it is correct that this matter should be investigated and decided in the legal system and laws of the countries and not under the convention. The need for the price to be clear and certain in the Iranian civil law, which is based on the thinking of the Imami jurists, has also been accepted in this document, and basically, there is no conflict between the aforementioned contract and the domestic law, and it is possible to distinguish the appearance of this document from the legal standards. He resolved the domestic issue by referring to a correct and proper interpretation of the word "gharar", the correct analysis of the turn of articles 14 and 55 of this document and also paying attention to the distinction of legal systems in the world and she confirmed the validity of this category of transactions.