In the long history, China has accumulated a large number of excellent traditional cultures, especially folk-art elements, which are very rich in content and are good design materials and inspiration sources. With the development of China's economy and society, people's requirements for interior decoration have become higher, so multimedia graphic design to meet users' personalized needs is a typical implicit optimization problem. Therefore, this paper combines folk art elements with modern digital processing technology and interior design of image processing, and at the same time, the improved interactive genetic algorithm introduces users' subjective evaluation into the design process, allowing users to participate in the design work. Experiments show that the algorithm can effectively meet the personalized needs of customers in the process of graphic design. It has played a positive role in the integration of national art and modern interior design and the embodiment of national characteristics in modern multimedia design.