The purpose of this study was to identify the structure and characteristics for the reproduction of the armor in the Unified Silla period, and then reproduce and utilize it as a cultural content. In the armor reproduction project excavated from Jaemaejeong, Gyeongju. Jaemaejeong armor is consisting of Singap (身甲, body armor), Sanggap (裳甲, hip armor), and Sangbakgap (上膊甲, upper arm armor) at the time of excavation. Unlike the armor of the Three Kingdoms period, Singap and Sanggap are separated. Singap is Yangdangsik (裲襠式, side opening method) and Gyunggap (頸甲, gorget) was not unearthed, Sangbakgap was divided into a part that protects the left and right upper arms and a part that protects the chest, so that the unexcavated head and neck cover of the helmet can be protected to the shoulder. In addition, in the case of Chalgap (札甲, lamellar armor), the Oejungsik (外重式, folded from outside to inside) is mainly used, but it is peculiar that Naejungsik (內重式, folded from inside to outside) is used in Sangbakgap of Jaemaejeong armor. It is presumed that this was used as a method to ensure that the armor were closely attached to the human body. In order to design with the parade armor of Gochwidae in Gyeongju based on the reproduced Jaemaejeong armor, the designer’s imagination and historical work of the times were involved due to the characteristics of performance costumes. Reproduced armor as a cultural content should be considered indispensable to simplify and lighten clothing suitable for performances based on the excavated historical armor.