Abstract: Objective: To sort out the works in history, describe the historical process, and summarize the historical achievements of
the scientific expedition for Cangshan mountain and Erhai lake, and put forward suggestions for future scientific expedition. Methods:Based on retrieving and investigating literature and taking the history of biological science expedition as the main line of discourse, the history of scientific expedition for Cangshan mountain and Erhai lake was divided into different stages according to the characteristics of the development process of Chinese society since modern times, and the specific works and main achievements of each stage were elaborated. Results: The modern scientific expedition for Cangshan mountain and Erhai lake region was initiated in 1882 by Westerners represented by Père Jean Marie Delavay. In 1919, Zhong Guanguang（ also known as Tsoong Kuan-Kwang） came to Cangshan mountain and collected specimens, which was the first time for Chinese to investigate Cangshan mountain and Erhai lake. So far, the scientific expedition in this region has gone through four main development stages, i.e., the initial stage before the founding of the People′s Republic of China （before 1949）, the early period of the People′s Republic of China （1949-1977）, the first 20 years of reform and opening up（ 1978-2000）, and the latest 20 years（ 2001 to present）. After more than 140 years of accumulation of scientific expedition, we have a systematic understanding of the species resources and its distributions of plants, macrofungi and some animal groups （i.e., mammals, birds, fish, and some insects） of the Cangshan mountain and Erhai lake, as well as a comprehensive understanding of the physical geography, geology, and ecological environment resources in this region. The plant hunters represented by George Forrest had brought back many plant germplasm resources from this region to Europe and the United States, which greatly promoted the development of horticulture and landscape architecture and the associated industry in Western countries. Conclusion: The scientific expedition for Cangshan mountain and Erhai lake has a long history and rich contents, which is rare in China, and had made significant contributions to
the development of modern biology, especially botany. In the future, it is necessary to further strengthen investigations in biology, ecology, and environmental science, which aimed at answering important questions, and thus promote the progress of science. For instance, the protection and restoration of biodiversity and ecological environmental, and the sustainable development of human society in the context of intensive human activities and global change. Furthermore, to coordinate the requirements of the management of national nature reserves and the social needs of the application of technology for resource exploitation and utilization, thereby making Cangshan mountain and Erhai lake better serve the development of regional economy and society.

Key words: Cangshan mountain, Erhai lake, plant hunter, plant explorer, scientific expedition, history of science