As the first visual element perceived in brand identity, color plays a crucial role in brand marketing. It shapes consumers’ attention, emotions, and trust, and is closely related to brand personality, quality judgments, and purchase intentions. Drawing on literature analysis and typical brand cases, this study examines the mechanisms through which color functions in brand marketing and compares color strategies across different brands. Using Coca-Cola, Apple, Starbucks, and Xiaomi as representative cases, it analyzes their primary brand colors, auxiliary color systems, and cross-media applications, and identifies three key pathways: visual identification mechanisms, emotional and associative mechanisms, and value perception mechanisms. The results indicate that red reinforces a vibrant brand image and stimulates impulsive consumption; black, white, and gray convey a sense of premium quality and professionalism; green evokes associations with nature and health; while orange and other warm tones enhance perceived friendliness and approachability. On this basis, the study proposes strategies such as constructing coherent brand color palettes, ensuring cross-channel consistency, and adopting emotion-oriented color applications, in order to provide practical guidance for brand visual design and marketing communication.