The traditional Chinese painting theory "coloring according to Categories" emphasizes the selection and collocation of colors based on the categories and essence of objects, embodying the dialectical unity of objective realism and subjective freehand brushwork. From an interdisciplinary perspective, this paper combines theories of literature and painting, takes blue-green landscape painting as the basis, and explores the value of the "coloring according to Categories" theory for Chinese composition teaching. The first part reveals the current situation of composition teaching and expounds the possibility of establishing interdisciplinary connections between traditional painting theories and Chinese writing teaching. The second part starts with specific grand and light blue-green landscape paintings to explore the teaching approaches of "color application" as a specific technique. The third part deeply excavates the multidimensional values of "using traditional aesthetic wisdom to address contemporary writing dilemmas".