[Objective]To study the water stored in bamboo stump on the physiological characteristics of different aged Phyllostachys edulis (moso bamboo) under drought environment so as to lay a theoretical basis for the management and water-saving irrigation measures in the context of climate change. [Method]1-year-old,2-year-old and 3- year-old moso bamboos were selected as the research object. Simulating drought environment by the method of covering film,9 sample plots with same size in the moso bamboo forest (10 m*20 m) were set up. The plots were trenched and the rhizomes were cut to block moisture transport from the surrounding soil. 3 irrigation treatments were set,i. e. T1 (12 stump with water storage),T2 (18 stump with water storage) and the CK (0 stump with water storage). Each treatment was performed in triplicate to research the physiological responses of bamboo at three age levels with the different water amount stored in the stumps. [Result]The result showed that under simulated drought environment,the net photosynthetic rate (Pn) and transpiration rate (Tr) of 1-year-old,2-year-old and 3- year-old moso bamboo decreased significantly with the water amount stored in the stumps decreased. The max decline of Pn and Tr in 1-year-old,2-year-old and 3-year-old moso bamboo reached 74.35% and 73.08%,59.14% and 36.62%,60.47% and 61.54%,respectively. The contents of Chlorophyll a (Chl a),Chlorophyll b (Chl b) and Carotenoid (Car) in moso bamboo leaves decreased significantly. The Chl a,Chl b and Car contents of 1-yearold and 3-year-old moso bamboo showed significant differences (P < 0.05). The Chl a content of 2-year-old moso bamboo showed significant difference,but there was no significant difference in the content of Chl b and Car (P < 0.05). And the Chl a /b in the three aged moso bamboo were not significantly different (P < 0.05). The superoxide dismutase (SOD),catalase (CAT) and peroxidase (POD) activity as well as the malondialdehyde (MDA) content in moso bamboo leaves increased significantly (P < 0.05). There was a positive relationship between the photosynthesis,the photosynthetic pigment content of moso bamboo and the quantity of moso bamboo stumps,while the MDA content and SOD,CAT and POD activity were negatively related to the quantity of moso bamboo stumps. [Conclusion]This study showed that increased water storage in moso bamboo stumps could significantly improve the photosynthesis of moso bamboo,increase the accumulation of photosynthetic products and leaf photosynthetic pigment content and decrease MDA content and SOD,CAT and POD activity in a drought environment.