This paper explores the visual language characteristics of colors in illustrations of primary school Chinese textbooks, focusing on three dimensions: basic visual attributes, emotional expression, and educational adaptation. The colors of the illustrations are mainly characterized by medium-high lightness and low purity, with hue matching adapted to the text scenes; positive and negative emotions are conveyed through color tone combinations, and neutral colors play a coordinating role; the color design is gradiently adapted to grade-specific cognition, responds to text content, and undertakes the function of aesthetic enlightenment. The research shows that the colors of textbook illustrations need to conform to the visual development and cognitive characteristics of primary school students, realize the unity of information transmission, emotional resonance, and educational aesthetic value, provide visual support for Chinese teaching, and help students deepen text understanding and cultivate aesthetic literacy.