Abstract: To investigate the photoprotection of waterwater circulation in ginger leaves, the effects of different treatments such as natural light + water control (T₁), shading 50% + water control (T₂), natural light + 10 mmol·L^-1 IA (T₃), shading 50% + 10 mmol·L^-1 IA (T₄) on leaf chlorophyll fluorescence parameters, Mehler reaction and the activities of SOD, APX of potted ginger were studied. The results showed that the P_n and F_v/F_m of ginger leaves in T₃ and T₄ reduced constantly, but that of T₁ and T₂ had no significant change during treatment. For example, at the ninth day after treatment, the P_n of T₃ and T₄ decreased by 64% and 33.2% respectively, and the F_v/F_m decreased by 16.5% and 10.9% respectively, while Mehler reaction of T₃ and T₄ increased by 139.4% and 72.6% respectively, the activity of SOD and APX were significantly higher than those of the controls. At the sixth day after treatment, the leaf P_n and F_v/F_m in all treatments reduced significantly at noon, but Mehler reaction and the activities of SOD and APX increased markedly, and the largest amplitude was observed in T₃, followed by T₄, and then T₁ and T₂. So, it was clear that Mehler reaction and the activity of reactiveoxygen scavenging enzymes increased when leaf P_n was inhibited by exogenous IA. The results suggested that waterwater circulation played an essential role in dissipating excessive light energy of ginger leaves.