Building design roof cornice waterproof device

The utility model belongs to the field of eave waterproofing, and particularly relates to a building design roof eave waterproof device which comprises a water receiving tank, a first fixing block is fixedly installed on the surface of the water receiving tank, the inner wall of the first fixing block is rotationally connected with a cleaning mechanism, and the cleaning mechanism comprises a rotating rod. The rotating rod is rotationally connected to the inner wall of the first fixing block; by arranging the cleaning mechanism, the purpose of cleaning leaves and other sundries falling into the water receiving tank can be achieved, by arranging a reciprocating lead screw and a cleaning brush, when a first transmission belt is pulled, the first transmission belt drives a rotating rod to rotate, so that a first belt wheel drives a second transmission belt, and under rotation of the second transmission belt, the leaves and other sundries fall into the water receiving tank. And the second belt wheel can drive a re