Abstract: One the most important and challenging at issue matters in private international law about nationality is the nationality status of undetermined nationality people that is a challenging topic because as it is clear some lawyers knows the nationality as a political and spiritual relationship which linking a person to the certain government. While, according to paragraph 1 of Article 976 of the Civil Law that indicate this subject: “All residents of Iran are considered as Iran’s citizen excluding certain persons who their foreign nationality is definite. Foreign nationality from those is definite that their nationality documents not protests with Iran’s government.” In this study, due to the researchers scientific indigent, we attempt to clarify the legal status of these persons. And as regards, paragraph 1 of Article 976 of the Civil Law will give evidence in confirmed ambiguities but we are confronted onstream with items which had been behaved with such cases completely inconsistent and we seek to discover this lack of attention to the legal status of undetermined citizens that is from material and political consequences?! And to what extent is related with our ideas and opinions which is reflected in the constitution?! And also, how the principle of respect for the rights of foreigners is observe in our country?! Protest situation of government about these people should be unlimited and from a position of strength?