Iranian governments from the Safavid to Pahlavi period had many differences and conflicts with the Ottoman state and its heir, Turkey, the lack of precise demarcation of borders by the two countries from Mount Agri (Ararat) to Shatt al-Arab was one of the aggravating factors of this issue. With the formation of the republican government in Turkey and the Pahlavi government in Iran, the parties took serious efforts to resolve the border disputes, especially in the case of Mount Agri. Using historical documents and texts and on the basis of descriptive-analytical method, the present article tries to answer the question, what was the position of Agri Mountain in the relations between Iran and Turkey during the first Pahlavi period? The findings show that the rebellion of the Kurds around Ahri Mountain in 1306 against the Turkish government made the important strategic and security position of this mountain on the borders of Iran and Turkey more obvious to the Turkish side. The fact that the border lines were not clear gave the Turkish side the necessary excuse, and under the pretext of ensuring the security of their eastern borders, they demanded the annexation of the small Agri Mountain, which in the previous agreements passed between the two sides of the border line from its head line, to the territory of Turkey. Therefore, after the end of the Kurdish rebellion, with the neglect of the Iranian authorities, agreements were signed between the Iranian and Turkish sides, according to which the small mountain of Agri was exchanged for a plot of land from the Turkish government.