Ko Hui (1560–1615), a military official from the mid-Joseon period, received the title of Meritorious Subject of Hoseong in 1604 for escorting the king during the Japanese Invasions of Korea. Three portraits, one in full-length and two in half-length, believed to depict Ko Hui among the artifacts (20 items in 215 pieces) passed down within the Jeju Ko clan in Buan were designated as treasures. This portrait presents a full-length view of Ko wearing a black dallyeong (round-necked robe) and a samo (black gauze hat) while seated in an armchair in a three-quarter orientation with his face turned slightly toward the right. His features are delineated with brown lines, and his lips are painted in red. This work is a typical example of seventeenth-century images of meritorious subjects, as demonstrated by the colorful Chinese carpet on the floor and the feet spread out in a fan shape on top of the footstool.