Flood prevention alarm device

The flood prevention alarm device comprises a monitoring assembly, and the monitoring assembly comprises a connecting plate, a connecting rod, a cylinder body, a through hole, an infrared sensor, a guide rod, a sliding rod and a floating ball. The bottom of the connecting plate is fixedly connected with a connecting rod, the bottom of the connecting rod is fixedly connected with a cylinder, through holes are evenly formed in the outer side wall of the cylinder, and an infrared sensor is installed on the top of the inner side wall of the cylinder. The floating ball is protected through the cylinder body, floating objects in water are prevented from entering the cylinder body to influence the movement of the floating ball, the floating ball can work normally, meanwhile, the cylinder body can slow down the water flow speed and reduce the influence of stormy waves on the floating ball, and when the floating ball moves up and down along with the stormy waves, the infrared sensor is used for detecting the distance