Traditionally, the issue of "law governing private international contracts" has long been one of the most significant issues of laws conflict and at present, its importance has increased with the development of trade and commerce. The Iranian legislature has also addressed this issue in the second volume of the Civil Code and has laid down Article 968 of this law as a rule regarding transactions, and apparently accepts the theory of "rule of law at the conclusion place" over contractual obligations, in exceptional cases. It also respects the will role of parties in recognizing the governing law. However in recent years, in light of recent developments in international law, legislators and, in some cases, jurisprudence have aligned them with legal doctrine and taken steps to adopt the latter theory. An examination of the French legal system indicates that by acceding to the 1980 Rome Convention, France has accepted the most important rule in Article 1 of the Convention, which is the "freedom of contracting parties to private international law to choose the law governing contractual obligations" and, except in cases the exception mentioned in the following articles of this Convention, this rule has caused a great change in the contract law of this country; However, before that, the judiciary of this country, with emphasis on the principles of free economy and capitalism, has more or less paid attention to this important and valuable rule.