Abstract: Aiming at the unique national traditional architecture formed by the Li ethnic in Hainan Island during the long historical development, the gene expression mechanism of architectural culture is introduced in accordance with the principle of biological gene inheritance. This paper analyzes the evolution process of the traditional architecture of the Li ethnic in Hainan Island, explores the inheritance mechanism of architectural cultural genes (the internalization, internalization and externalization of cultural genes) throughout it, and reveals the relationship between architectural cultural genes and traditional architectural features (site selection, layout, structural space, decoration, etc.). Understand the formation and evolution of traditional Li ethnic architecture from a new perspective, and examine the problems faced by traditional architecture and the future development direction. It is hoped that it can be used as a reference for the future research and protection of traditional buildings of the Li ethnic in Hainan Island. This paper understands the formation and evolution of traditional architecture of Li ethnic from a new perspective, and examines the problems faced by traditional architecture. From the perspective of imitating biological genetics, the prospects for the future of traditional buildings are put forward, hoping to provide a reference for the future research and protection of traditional architecture of Li ethnic in Hainan Island.