Castanopsis fissa is an evergreen broad-leaved species of the cone genus Castanopsis in the family Fagaceae, which is widely distributed and is an excellent native species in Guangdong Province of China. This species has a well-developed root system, excellent soil-fixing power, and better soil and water conservation ability and has the characteristics of barren tolerance, strong sprouting power, abundant and easily decomposed dead leaves, etc. Therefore, C. fissa is not only a pioneer species for postdestruction sprouting forests but also a highly potential ecological public welfare forest tree species. Moreover, due to its beautiful shape, wide canopy and various colors, it has become an ideal tree for landscaping and ornamental purposes. However, there is a basic gap in knowledge in the reports on the drought resistance or drought tolerance genes of C. fissa. Based on the above details, in this study, 2-year-old C. fissa seedlings were used as the study material to investigate the physiological response under drought stress by a potted drought experiment, and we also compared and analyzed the differentially expressed proteins (DEPs) under different periods of drought stress by TMT quantitative labeling protein to prepare a preliminary study on the physiological response and proteomic mechanism of C. fissa adaptation to drought stress.