This study is based on the theory of film semiotics and employs qualitative research methods. Taking the "Nezha" series of films directed by Jiaozi as an example, it delves into the application and significance of CG technology in folklore-themed films. Through the lens of semiotics, the study analyzes the visual, cultural, and narrative symbols in the films, revealing how CG technology shapes the visual style, inherits folklore culture, and drives the development of the story. The research adopts case analysis, textual analysis, and audience interviews to deeply interpret the symbolic elements in the films and explores their acceptance and cultural significance based on audience feedback. The findings indicate that CG technology not only enhances the visual appeal of the films but also effectively inherits and promotes Chinese folklore culture through the creation and use of symbols. However, challenges such as the diversity of symbol interpretation, in-depth exploration of cultural connotations, and differences in audience understanding also exist. Based on these findings, this paper proposes suggestions for optimizing symbol design, strengthening cultural research, and improving audience guidance. These recommendations aim to provide theoretical support and practical guidance for the application of CG technology in folklore-themed films, to promote the high-quality development of this genre, and to further promote excellent Chinese folklore culture.