The work aims to design the cultural and creative products in Shenyang Palace Museum by AIGC based on Peirce semiotics theory and explore the development and application of AIGC in the cultural and creative industry in the era of intellectual media. A new cultural and creative design model of Shenyang Palace Museum was derived by expanding and introducing AIGC technology on Peirce's basic model of semiotics. By sorting and classifying the cultural elements of Shenyang Palace Museum, the symbols of different categories of cultural elements were coded, the needs of target user groups were obtained by means of questionnaire survey, and the results of questionnaire survey were analyzed to decode the user experience of products, thus guiding the design of cultural and creative products in Shenyang Palace Museum. The final design practice was divided into three parts, including the product realized by AIGC code introduced based on the cultural and creative design model of Shenyang Palace Museum, AIGC code generation of cultural and creative products under the description method of Fu, Bi and Xing and AIGC code generation of cultural and creative products under reverse requirement description. On this basis, the results of three design practices were compared and analyzed. The design practice showed that the application of AIGC technology in cultural and creative design could broaden designers' design thinking, improve the innovation of cultural and creative products, and meet users' spiritual and cultural needs. At the same time, cultural and creative products with higher human-AI "communication" frequency were more in line with user needs, and the presentation and design of various "human-machine" schemes were more conducive to realizing higher human-machine value co-creation, and the three design practices also theoretically optimized the design of cultural and creative products by AIGC under Peirce semiotics theory. At present, AIGC still has some problems in the generation of cultural and creative products. Under the guidance of Peirce semiotics theory, it can improve the level and efficiency of cultural and creative design to a certain extent, contribute to the development of the cultural and creative industry of Shenyang Palace Museum, and provide new ideas for subsequent scholars to study AIGC and cultural and creative design.