The purpose of this study is to understand the architectural space of Chimjeon (寢殿), the King's Bedroom, and Backyard, in the early Joseon Dynasty. The Royal palace can be divided into three parts, political space for King, living space for King and his family and government office. So first, we should to understand the characteristics of each space in the Royal Palace. Up to now we have looked at the architectural space of the King's Bedroom in the central area and Backyard in Gyeongbokgung (景福宮), one of the Royal Palace, the result of this study is as followings. Cheonchujeon (千秋殿) and Manchunjeon (萬春殿) were not both sides of Sajeongjeon (思政殿), were on the north side of Gangnyeongjeon (康寧殿) Gangnyeongjeon was not a bedroom for the King and Queen, only for King. Bedroom for Queen was located another space in the Royal palace. There was Hamwonjeon on the west side of Koytaejeon. Jamidang and Cheongyeonroo were on the right side of Koytaejeon The Backyard on the north side of Gyeongbokgung had a wide area for horseback archery and the practice of battle formation The arrangement of the King's bedroom in the central area was assumed like as the Fig 7. and Fig 8.