Abstract: In order to study the characteristics of water level distribution along the central axis of bend flow in open channel, a mathematical model based on maximum entropy theorem was constructed based on the data of physical model test. The results showed that the water level has a certain decreasing trend when the inlet and outlet ends of the bend section are connected by a straight line section. Through the error analysis on the distribution along the curve axis, we can see that the model has certain accuracy, stability and representativeness, which provides a new idea for the curve flow movement.