The invention discloses a corridor-type water pollution early warning device, which includes a corridor-type fish tank, a bracket and a camera, the bracket is arranged on the side of the corridor-type fish tank, the camera is arranged on the bracket, Collect the image inside the corridor type fish tank; the corridor type fish tank includes a rectangular cylinder body, a water inlet, a water outlet, a water baffle and a barrier column, and the water inlet and the water outlet are arranged on the tank At the side wall of the body, the length of the baffle plate is less than the width of the cylinder body, and they are staggered and vertically arranged inside the cylinder body, and the cylinder body is equally spaced into at least 3 connected corridors; The barrier column is arranged between the grid and the side wall of the cylinder, and the distance between the two barrier columns is 2-3 cm. At the same time, the invention also provides a corridor type water pollution early warning method. The invention has the advantages of simple structure, convenient use, low cost, high sensitivity, straight pipe observation, timely and accurate monitoring of water quality, and can be used for rapid early warning of sudden water pollution events and large-scale water quality monitoring.