The invention discloses a rainproof member for the top part of a steel-structure building wall hole, comprising a rainproof component, a decorative component and a connecting plate. The rainproof component comprises a flat plate which transversely extends to cover the bottom of a sandwich plate at the top of a hole, wherein the two transverse sides of the flat plate are respectively sealed with an upwards vertically-extended anti-drip plate and a downwards vertically-extended anti-seepage plate. The connecting plate is vertically arranged and located on a flat plate at the opposite side of the anti-drip plate, wherein an installing hole for fixing with the bottom of the external plate surface of the sandwich plate is arranged on the connecting plate. The decorative component is covered onthe connecting plate and the anti-seepage plate. In the invention, by adopting the technical scheme that a rainproof component is arranged on the bottom of a sandwich plate, the anti-drip plate of the rainproof component can prevent rain from flowing indoors along the supper surface of the plate, and the anti-seepage plate of the rainproof component can prevent rain from seeping indoors along thelower surface of the plate, thus good rainproof effect can be achieved.