Various types of curved wooden have always been used in traditional Korean architecture. One component is a curvaceous column with varying thicknesses, and the others are curved beams or girders that are needed to support the roof and present diverse curvature. By examining the historical alteration of the parts and shapes of these curved members, it is possible to identify the sustainable aspects of Korean traditional architecture and infer the influence of the historical background on forming the sustainability of the architecture. To be specific, while the Goryeo Dynasty (10–14 C) showed an aesthetic summit of temple architecture in terms of extravagant curved wooden members precisely calculated and designed under the influence of Buddhism and aristocracy, the early Joseon Dynasty (15–16 C) presented restrained curve forms of wooden members with fewer materials and a faster process due to Neo-Confucianism, which emphasized austerity. After tremendous social crisis and two wars, the mid-Joseon Dynasty (17–18 C) showed creative indigenous houses with naturally curved timbers, minimizing the manufacturing process and maximizing the pragmatic functionality of the space under the influence of the wars and Silhak (the Realist School of Confucianism). In addition, the late Joseon Dynasty (19–20 C) presented office buildings with strengthened dynamic shapes of the naturally curved timbers as symbolic expression, which is an expanded concept beyond the functionality. In Korean traditional architecture, curved wood members have been used without interruption—although in varying degrees depending on social and economic situations—and have continued to be one of the characteristics of Korean architecture.