The present invention provides a self-cleaning suction filter including a filter mechanism and a sewage suction assembly. The sewage suction assembly is rotatably arranged at the center of a fine strainer and communicated with a sewage discharge cavity through a sewage suction pipe, and the sewage suction pipe is spacedly and fixedly provided with a plurality of “T”-shape suction nozzles for suctioning deposits on the inner wall of the fine strainer. The self-cleaning suction filter further includes: a sand collection cavity arranged at the tail of the fine filter cavity and communicated with the fine filter cavity; and the coarse filter cavity, the fine filter cavity, and the sand collection cavity descend in height. Water are automatically collected in the sand collection cavity and discharged in time, thereby ensuring the stable filter function after the filter is used for a long time.