The Theory of Singing is a theoretical work that classifies and studies the art of vocal music by musicians of the Yuan Dynasty in China. This paper places the work in the context of the history of Chinese folk vocal music, outlines the development of Chinese folk vocal music, the aesthetic thought of Chinese folk vocal music, the development of folk vocal music in the Yuan Dynasty, and the concept of folk vocal music education in the Yuan Dynasty, and examines the position of the work in these rough lines. At the same time, the research results are more comprehensive than those of previous studies, and the significance of the work is studied in relation to the theory of Chinese folk vocal music performance, so that the research results are more relevant.