Water level monitoring is a key issue in water conservancy construction. In order to grasp the water regime in time and prevent flood disasters, an intelligent image water level recognition system solution is proposed After using traditional image algorithms for image preprocessing of water gauge images in various situations, the deep learning water level recognition algorithm based on YOLOv4 is used to train the collected images to achieve automatic water level recognition.. Experimental results show that the deep learning water level recognition algorithm based on YOLOv4 can effectively read the current water level through the water scale image, and the algorithm error is only about 1~2cm, which meets the requirements of engineering water level monitoring error.