Abstract
This study focuses on the power coding and hierarchical metaphor in the symbol system of ancient Chinese costumes. With the help of Pierce's Semiotics Theory as an analytical tool, it explores how the abstract power order is transformed into material symbols by the elements of color, pattern, material and shape. The study found that ancient costumes constructed a set of symbol system through color dictatorship, pattern metaphor, material regulation and shape constraints, and its power coding mechanism has the characteristics of icon (such as the visual similarity of sun and moon patterns), index (such as the causal relationship between complement and official rank) and symbol (such as the ritual agreement of dragon patterns). Pierce's interpretive term theory also further reveals that dress symbols in physical practice and ritual performance will realize the reproduction of power meaning through the hierarchical transformation of direct, dynamic and final interpretive terms. The author hopes that this study can be helpful to the semiotics of Chinese ancient traditional costumes.