This study investigates and reproduces the costumes of the dong-gi(童妓) who participated in the Seonyurak jeongjae(船遊樂) during the 1848 Mushingjinchan(戊申進饌) ceremony, hosted by King Heonjong. Mushingjinchan was a significant national event that reaffirmed the authority and tradition of the Joseon royal family. Unlike the well-documented costumes of female performers and the Cheoyongmu dance, the costumes of the dong-gi have received relatively little scholarly attention. This research focuses on the costumes based on records of the Seonyurak jeongjae, analyzing relevant documents such as Dobyeong and other period sources, including the Akhakgwebeom(樂學軌範). Discrepancies in the costume diagrams, textile usage, and quantities noted in the Mushingjinchan records required the reconstruction of garments including danui(丹衣), sang(裳), malgun(襪裙), and dae (帶). The dangui(唐衣) was also created based on the Gongnyeong records. The danui was made from green-patterned silk(草綠花紋甲紗) and red-patterned silk(紅花紋甲紗), with white silk(白花紋甲紗) for the sleeves Edge. The sang was crafted from red and green silk, with a decorative golden lotus flower and leaf design on the suryeong. The malgun and dae were made from red silk and red satin, respectively, while the dangui(唐衣) used the same fabric as the danui. The reconstructed costumes were fitted on child models to show how they were worn. This study systematically organizes dong-gi costumes" composition and production process, providing a foundation for a deeper understanding of the late Joseon dynasty court dance costume and its culture. However, due to the lack of detailed historical records, some costume elements had to be estimated, and the reconstructions may differ from the originals. Some modern interpretations were also necessary for colors, materials, and patterns. The study also did not reproduce certain accessories such as hwagwan(花冠) and suchohe(繡草鞋), which leaves room for future improvements. Future research will study various ceremonies and costumes of the late Joseon period, aiming to improve the accuracy of costume reconstruction. This study will allow for a more comprehensive organization of costume types and their evolution, leading to enhanced recreations of court dance costumes.