The ranking belts for Joseon dynasty officials that are based on references and relics are studied in this paper in terms of architecture, detailed names, and structural changes according to different time. Officials' uniforms consist of hats, clothes, belts, and shoes. Among these, the belt is an important sign that represents the wearer's ranking. The ranking belts of the Joseon dynasty which were brought from Ming at the late stage of the Koryo dynasty became classified as the following four classes : Seo-dai(a rhinoceros' horn, 犀帶), Gum-dai(gold, 金帶), Eun-dai(silver, 銀帶), and Heug-gag-dai(black horn, 黑角帶). A ranking belt consists of a basic belt body and a plaque that represents the wearer's rank. A plaque consists of 20 plates: three front-center plates that represent the Sam-tai(三台) constellation, six front-side plates that represent the Namduyug constellation(南斗六星), seven back plates that represent the Big Dipper(北斗七星), left side Bo(輔), right side Pil(弼), and a couple of Tamie at both ends. The architecture of the belt body; the basic frame for ranking belts, shows some differences between the former and the latter periods of the Joseon dynasty. In the former period, the belt had a pair of a buckle so that the wearers were able to adjust the belt size. But later, the belt didn't have the buckles to adjust the belt size and consequently it only performed a locking or unlocking function. Therefore, the belts in the latter period were longer than normal and one size fit all. In addition to the functional change of buckles, the shapes of the ranking belts show changes from the round shape to the square shape as time goes on.