Abstract: HAN An is one of the pioneers of modern forestry in our country. The Central Forestry Experimental Institute of the Ministry of Agriculture and Forestry was a forestry research institution established in the Republic of China, which played a great role in the national economy and people’s livelihood. From 1941 to 1949, HAN An served as director of the Central Forestry Experimental Institute of the Ministry of Agriculture and Forestry. He played a big part from the initial development period when the institute was limited to the later period when every business began to take shape, laying a solid foundation for the development of modern forestry. In the establishment stage, he revised relevant rules and regulations, set up organizational structures, recruited talents, and launched forestry publications. Later, when the institute moved to Nanjing for further development, he improved the institutional framework, gathered and trained forestry talents, launched forestry publications again, and cooperated with the Jingsheng Biological Institute. The seven years when HAN An worked for the Central Forestry Experimental Institute of the Ministry of Agriculture and Forestry are a brilliant period not only in the course of forestry development, but also of his lifetime. Looking back on this period of history, this paper explores its foundational role and historical significance in the course of forestry development.