The utility model provides a rain-proof sealing cover assembly which comprises a skin, wherein a cover is arranged on one side of the skin, a buccal frame is arranged on the lower ends of the skin and the cover, and a plug connector is arranged on one side of the cover; one end of the buccal frame is attached to the lower end surface of the skin, and the other end of the buccal frame is bent to extend downward, so as to form gaps together with the lower ends of the skin and the cover; an opening is formed in a position, at the lower end of the cover, of the buccal frame, an anchor nut is arranged in the opening of the buccal frame, and the cover is inserted into the anchor nut through the plug connector; a rubber blanket is arranged on the outer side of a position, between the cover and the buccal frame, of the plug connector; a sealant is arranged in a gap between the buccal frame and the lower end of the skin; and one end of the rubber blanket is connected with the sealant, so as to form seal. Compared with a traditional rubber blanket, the assembly has the advantages of reliable sealing performance and capability of rain prevention, so as to solve the problems of rain prevention and sealing of the cover on the skin.