This study focuses on the protection and inheritance of traditional national culture in online virtual character design. In the digital era, virtual characters have become an important visual means for individuals to express their ideas and cultural identity. The diversity of ethnic cultures is of great significance in enriching the culture of online communities and meeting the personalized needs of users. Dongba culture provides rich modeling and pattern materials for virtual image design with its unique visual elements. This study aims to analyze the development and characteristics of Dongba culture. And we establish a design method that combines Dongba culture with online virtual image desig to transform cultural information to design content. This study is based on the meme theory, which is derived from Darwin’s theory of evolution, and regards meme as the unit of information in culture, like the genetic information in DNA. With meme theory, we extracted the “genetic” factors of Dongba culture and categorized them into layers, and then created a genetic map of Dongba culture. In addition, the importance of each cultural factor in the design of the virtual image was calculated with the AHP method, and their proportion in the design was determined. The conclusion shows that the cultural information transformed based on AHP-modeling theory can be effectively applied to virtual image design, providing designers with a convenient way to obtain design elements of Dongba culture. This comprehensive research method not only provides a reference for the development of national culture on digital media but also supports the cultural diversity and personalized needs of online virtual communities.