Abstract: During Ming Dynasty the Korean geographical name“Baegdusan” indicated today’s Changbai Mountain. The Korean term“Changbaisan” did not necessarily refer to today’s Changbai Mountain but may have referred to Gwanmobong (located west of Kyongsong City, at an altitude of 2541 meters) in Northern Hamgyong-do, which is the second highest peak of the Korean peninsula. Gwanmobong was included in the three famous mountains of Hamgyong-do, and its status was much higher than the Baegdusan (present-day Changbai Mountain) which was still in the area that Jurchens occupied. To the Qing Dynasty, especially after the boundary demarcation by Mukden in Kangxi 51 (1712), the status of Baegdusan exceeded Gwanmobong. Baegdusan not only symbolized the cradle of Joseon Dynasty, but also developed an awareness that all the Hamgyong-do Mountains arose from the Baegdusan, when the Korean scholars call it“Baekdu daegan.” At the time of the Mukden demarcation, the area, which was not under Korean control, was located north of Hyesan, west of Musan, south of Changbai Mountain and north of Gwanmobong. Among these mountains, although the Gwanmobong was the main peak of the current Hamgyong mountain range, the geographical name“Changbaisan” of the Joseon dynasty, did not refer to the mountain system including the Hamgyong mountain range and Pujonyeong mountain range, it was also not the northern boundary of Korea during of Mukden demarcation.