This article is a study on the formation of Won (園) tombs, a unique burial type of the Joseon royal family, and its characteristic features. Won is a particular type of tomb which do not previously appear in Korea or China, occupying the status level in between the royal tomb ‘neung (陵)’ and the common tomb ‘myo (墓)’. It is less extensive than a royal tomb, but much more formal than a common tomb. Won did not exist from the beginning of the Joseon Dynasty but was invented by King Injo who wished to honor his deceased parents after he ascended the throne through a coup d’état. The first Won created by Injo soon disappeared because it became upgraded to a neung, but King Yeongjo took up the practice to honor his mother, who was the royal concubine of King Sukjong. King Yeongjo established his mother’s tomb as a Won and upgraded her shrine from being a Myo (廟) to a Gung (宮), and established the unique system of ‘Gungwonje (宮園制)’ for the shrine and tomb. King Gojong reformed this gungwonje system at the end of the Joseon Dynasty and expanded the scope of royals whose status was eligible for a won rather than a myo. Not only the biological parents of the king belonged to this category, but tombs and shrines for the crown prince, princess, and crown grandson were also recognized to be higher in status than those for normal royalty. As a result 21 won were created within the Joseon royal family, and 15 of them still remain intact till this day. The spatial arrangement between a neung and a won are basically very similar but the tomb mounds in won do not have retaining stones or stone guardrails. The differences can also be seen in the number of stone figures. Won do not have stone statues of military officials, and only have one pair of stone horse, sheep and tigers placed by the tombs mound, just half the number of stone statues which can be found in royal tombs of neung. Although the size of Won are much smaller than neung, they were established only in cases where the king came from a collateral line of family, or if the king’s birth mother was a concubine, or if the crown prince died early before ascending the throne, and therefore are valuable historic material in reading the history of royal lineage of Joseon.