Tea color, a critical quality attribute, consists of the color characteristics of dry leaves, infusion, and bottom of leaves, determined by the dynamic transformation of natural pigments and the formation of new chromophores during processing. This chapter systematically reviews the classification, chemical structures, and chromogenic mechanisms of color compounds in tea, focusing on catechin oxidation products (e.g., theaflavins, thearubigins, theabrownins), flavonoids (flavones, flavonols, and their glycosides), amino acid-derived pigments (e.g., Maillard reaction products, N-ethyl-2-pyrrolidinone-substituted flavan-3-ols), and other colorants (e.g., chlorophylls, carotenoids, anthocyanins). The coloration mechanisms are elucidated through molecular orbital theory (HOMO-LUMO energy gaps), absorption spectroscopy, and complementary color principles. Key factors influencing tea color, including processing techniques (fermentation, roasting, drying), pH, temperature, and ionic concentration, are discussed for their roles in modulating pigment formation and stability. Despite advances, structural elucidation of complex polymers (e.g., thearubigins) and their quantitative color contributions remain challenges. Future research leveraging molecular sensory science and advanced analytics is urged to decode structure-color relationships and optimize production for enhanced quality and functionality.