Korea and Japan are not only two neighboring countries, but both are closely related by culture. Therefore, we can find several points of similarity in both country`s myths as well as in their culture. Myth in both countries strongly appears as a culture factor in the northern part of Asia. This is especially true in the National Founding Myth in both countries where the factor of the advent of an ancestor as a delegate from heaven with sovereignty to establish a country appears commonly This sovereignty is related here as three kinds of divine treasure. Let us compare and discuss the three kinds of divine treasure mentioned in the Korean Dan Kuk myth and the Japanese Amatelas myth. First its very difficult to understand exactly the three kinds of sacred vessel mentioned in the Korean myth. This is because there is not any accurate record. Even in the present days many scholars published the results of their research on this point, but neither valid backing or agreed verification within academic circles was given. The three kinds of divine treasure in the Korean myth are briefly mentioned as follows: 1. mirror - sword - drum 2. god of wind -god of clouds - god of rain 3. mirror - sword - bell 4. God- humankind - nature In the Japanese myth the three kinds of divine treasure are clearly explained and are not only pointed out in records, but are still used as objects of inheritance in the coronation ceremony of the emperor and for members of the emperor`s family. The three kinds of divine treasure in Japanese myth are mirror, sword, and jade (a jewel). Comparing the three kinds of divine treasure in Korean and Japanese myths the mirror and the sword are the same, but the rest are each different. To understand the two myths I think it will be necessary first to understand the differences between the cultures and the religions of the people in both countries.