The utility model discloses a cutout of bridge floor rainwater utilizes device, including catchmenting mouth, downspout, infiltration well and the blind pipe that permeates water, catchment mouthful setting on the bridge floor, the upper end of downspout with the export of catchmenting mouthful links to each other, and the lower extreme of downspout inserts infiltration well, be equipped with the blind pipe that permeates water in the infiltration well, the greenbelt is introduced to the interior rainwater of the blind pipe that permeates water. The utility model discloses simple structure, whole is pleasing to the eye, does not take the space of laying of other professional pipelines, and usable bridge floor rainwater waters the greenbelt.