0. Our historical monuments can be classified as follows: - monuments of Mongolian language and Mongolian script, such as the text of Chinggis(1224), the order of Mangala van(1276); - monuments of Mongolian languate, such as the Secret History of Mongolia; - monuments of Mongolian script, such as records of foreign words written in Mongolian script. Today we will discuss about one of the monuments of Mongolian language ad Mongolian script in correlation with Korean researchers` study. 0.1 Among rare Mongolian historical monuments found in other countries we could mention the one in Korea. This monument is situated on the bank of Khan river and named Santian-tu in Mongolian, 삼전도 in Korean. This monument and the capital of Mongolia-Urga are of the same age. It was built in the year of 1639. It is 5 meters high and contains 28 rows of more than 500 words. We can note some features of the monument: 1. In 17th century Mongolians used grammatically correct Mongolian khudam script; 2. 88 per cent of words of the script in the monument matches with words of the Mongolian Secret History; 3. From the monument script we found some old forms of words uncommon for the 17th century.