Air suction valve for drainage pipeline

The utility model relates to the technical field of water supply and drainage equipment elements, in particular to an air suction valve for a drainage pipeline, which comprises a conducting part, an air suction cap and a water seal part. A vertical tube is arranged in the middle of the conducting part, and transverse tubes are fixedly arranged on the two sides of the vertical tube and communicated with the vertical tube and used for being connected with a drainage pipeline; the air suction cap is arranged at the upper part of the conduction part, is communicated with the conduction part and is used for sucking air when negative pressure is generated in the pipeline; and the water seal part is arranged at the lower part of the conduction part and is communicated with the conduction part, and air between the two transverse barrels can be separated through water seal. The air suction cap is provided with a valve clack structure communicated with the outside, and the valve clack structure can be opened for air su