In this study, we divided the portraits in the reign of King Seonjo into those which were created before and after the Japanese invasion. We then examined various aspect of costumes expressed in the portraits of meritorious vassals. To analyze official uniforms (Heuk-Danryeung), we examined the Samo height; the side wings' type and pattern; the Danryeung pattern; the Mu style; the processing method of lateral lines in Danryeung the rank badge and rank belt, the color of Dabho and Cheolrik, which were undergarment of Danryeung and Heuk-wa. The meritorious vassals' portraits, prior to Imran, were analyzed with a portrait of Han Eung-in, a Gwang-kuk Pyeong-nan meritorious vassals. The Samo was the highest of the Choson dynasties, and the cloud and treasure pattern was identified on the side wings. The Heuk-Danryeung was a dark blue(acheongsaeg) Danryeung of manja-shaped cloud patterns with a large outward wrinkled Mu, and it had a wild goose badge (second rank) and a Sabgeumdae. It did not coincide with the Pumgye(Jaheondaebu) recorded in Gugjo-inmulgo. Reddish Dabho for Dangsang-kwan, green Cheolrik which was undergarment of Danryeung, and Heuk-wa. were identified. After the invasion of Japan, portraits of Hoseong, Seonmu, and Cheong-nan meritorious vassals were analyzed through eighteen portraits, including Lee Hyeon-bok. After the invasion of the Japanese, the height of the Samo's top was much lower and the width of the side wings was wider than before the invasion of Japanese. The Heuk-Danryeung was a dark blue (acheongsaeg) Danryeung of manja-shaped cloud patterns with a stretching backward Mu. Rank badge and rank belts were almost identical with the record, but there were two exceptions (Sin-jab and Kim, Sae-sin). Therefore, it was reaffirmed that the meritorious vassals' portraits were drawn by the Pumgye at the time of appointment. Among the undergarments of Heuk-Danryeung, green Dabho(11), blue Dabho(4), reddish Dabho(3), and blue Cheolrik(10), green Cheolrik(6), reddish Cheolrik(1), and yucheongsaeg Cheolrik(1) were identified, However, it is suggested that the Dabho of Hoseong, Seonmu, and Cheong-nan meritorious vassals should be the reddish Dabho of Dangsang-kwan, which is the same as the previous Imran, and a green Cheolrik.