The increasing demand for innovative design professionals, coupled with sustainable design practices and the appreciation for handcrafted traditions within China's digital economy, necessitates the incorporation of intangible cultural heritage, such as Mianzhu New Year paintings, into vocational graphic design education. This integration is essential for supporting Sustainable Development Goal 4 (Quality Education), SDG 11 (Sustainable Cities and Communities) and achieving a balance between technical training and cultural preservation. This research seeks to investigate successful integration pathways and assess their influence on students' capacity to convert historic materials into contemporary design languages, as well as the practical applicability of their creations under the two hypotheses. An experimental methodology using project-based learning, varied resources, and digital tools was implemented throughout an 8-week intervention, comprising a control group utilizing standard lecture-based instruction and an experimental group consisting of 90 sophomore graphic design students from Sichuan Tianyi University. Data were gathered by structured questionnaires, semi-structured interviews, and design work analysis, and were examined in terms of creative design capability, technique application, digital tool proficiency, inheritance willingness, cultural value cognition, and dissemination behavior. T-tests and correlation analysis were employed in conjunction with descriptive statistics for the analysis. This research presents a replicable model for vocational colleges to incorporate local intangible cultural heritage into their curricula, enhances students' dual competencies in skills and cultural literacy, and supports the living preservation of Mianzhu New Year paintings. A strong positive correlation was found between creative design ability and awareness of intangible cultural heritage, with the experimental approach demonstrating significance at p<0.001...