The rainwater hopper belongs to the branch of the metal falling-water system, which is located at the entrance of the roof rainwater from the gutter into the rainwater pipe. The rainwater hopper has a rectifying grid device, which can quickly eliminate roof rainwater. The grid has the rectifying function to avoid the formation of too large vortex, stabilize the water level in front of the bucket, reduce the aeration to quickly eliminate roof rainwater, snow water, and can effectively block larger debris. It is used with gutter, downpipe collocation.