The accumulation of dry matter in plants depends on the canopy photosynthetic rate, which is closely related to single leaf photosynthetic capability. Leaf photosynthesis is also highly correlated with its water content. Compared to soil water content, leaf water content can directly reflect crop growth and development and might be the best index for showing the degree of water profit and loss. Leaf water content and photosynthesis at different positions have been investigated in a number of studies. However, there have been fewer reports on the change in leaf water content (LWC) at different positions and its relationship with photosynthesis under consecutive drought stress. In this study, six different watering treatments were designed to simulate the response of leaf characteristics at the different leaf positions of summer maize "Zhengdan 958" that had been subjected to persistent drought. The simulated experiment was conducted in Baoding City, Hebei Province, northern China. After analyzing the change in leaf water content (LWC) at different positions and its relationship with net photosynthesis, the results indicated that the change in leaf position in summer maize can influence the falling rate for leaf water during consecutive drought periods and the estimated maximum leaf water content. The falling rate for leaf water and the estimated maximum leaf water content in Leaf 1 were more than in Leaf 3 and Leaf 5. When leaf photosynthesis (P_n) fell to zero (the lowest leaf water content that can maintain net photosynthesis), the leaf water contents of Leaf 1, Leaf 3, and Leaf 5 increased as the leaf position increased. This indicated that the photosynthesis response to leaf water content was different at each position. The leaf water content of Leaf 1 had strong relationships with soil water content and photosynthesis. The minimum leaf water content that could maintain net photosynthesis in Leaf 1 was lower than all the other leaf positions, which meant Leaf l had better drought tolerance. This suggests that the use of Leaf 1 in drought monitoring could be developed further in the future. These results will contribute to the accurate simulation of canopy photosynthesis and to the development and monitoring of drought in summer maize.