Abstract: In order to explore the physiological change of leaf senescence of bamboos after anthesis, Shibataea chinensis was taken as experimental material. The results showed that the contents of chlorophyll, soluble protein and soluble sugar of bamboos after anthesis decreased gradually, which were always lower than those of the control group during the experiment. But the changes in ratio of soluble sugar content to soluble protein, and MDA content increased gradually, which were higher than those of control group throughout the experiment. With the prolongation of testing time, the variation range of indexes and the gap compared to the control indicated that leaf senescence of bamboos accelerated gradually after anthesis. At the early flowering stage, the SOD activity of flowering bamboo was significantly higher than those in the control group, but the POD and CAT activities were significantly lower. At the late stage, the change degrees of protective enzyme activities were significantly higher than those of control group, which showed the imbalance of protective enzyme system. We guess that production of a great quantity of active oxygen and imbalance of protective enzyme system led to the destruction and degradation of the structures and functions of biomembrane and biomacromolecule and the aggravation of the lipid peroxidation, which may be one of the main cause that accelerates the leaf senescence of bamboos after anthesis.