irjand's handwoven carpets are recognized as one of the authentic Iranian types, and among their diverse designs, the Sa'di carpets have attained a special status. This design, which is rooted in the ancient traditions of design and aesthetics in eastern Iran, is distinguished by its characteristic layout and medallion (toranj), as well as the harmony of its colors and their visually pleasing coordination with the motifs. The analysis of color arrangement in these carpets not only contributes to a deeper understanding of their aesthetics and symbolism but can also reflect the conventional criteria of color application in the carpets of this region. The present study is fundamental in nature and, employing a descriptive-analytical approach, examines the dominant color spectrum in Birjand's Sa'di-design carpets. It demonstrates that colors such as lacquer-red, indigo (or dark blue), beige, and cream are the most frequently used, and that their combination with complementary colors, as well as the creation of various visual color contrasts, establishes visual balance. The objectives of this research include identifying and analyzing the color arrangement system in the Sa'di carpets of Birjand. Accordingly, the following questions are addressed: 1. What are the dominant and subordinate colors in the Sa'di-design carpets of Birjand? 2. How does the combination and coordination of colors in the Sa'di carpet contribute to the creation of visual harmony?