The traditional approach of states to grant nationality has been applied in discriminatory manner between parents, but the equality movement has fundamentally changed the approach of states in favor of parental equality. The main question of this article is what is the role of the mother in Iran` nationality law regarding the transfer of her nationality to the child? The Iranian legislature's approach in this regard was initially based on discrimination between Iranian parents in transferring nationality to their children, but gradually, this approach has been moving towards the elimination of discrimination. The Iranian legislature` approach in this regard should be examined in three different categories. In Civil code of Iran, the role of the mother was completely ignored. According to Single Act of 2006, in case of the child born in Iran of an Iranian mother and a foreign father, the nationality of Iran would be granted to the child. In 2019, this regulation was amended and children born abroad Iran are also granted Iranian nationality. But there is still a discrimination between the parents, because a child whose mother is Iranian and whose father is foreigner, will be granted Iranian nationality if it would not contrary to national security. Meanwhile, Iranian Nationality is granted to child born of Iranian Father and whose mother is foreigner unconditionally.