Film is an art form that combines sound and picture, and music, as a symbolic expression, plays an increasingly important role in films. In genre films, musical notation often has its own aesthetic value and ideographic function. As an important film genre, youth-themed films have formed a set of proprietary "systems" in the process of continuous development. Its function is not only to cooperate with the picture, but also to express the meaning and textual value of the music independently in the narrative process. Through the analysis of musical symbols in youth-themed movies, this paper attempts to clarify the ideographic mechanism of music in youth movie texts, interpret the main role of musical symbols as an interpretive link in the narrative process of movies, and make Chinese genre film music more vital.