The invention discloses a water filtering wall body of a fabricated all-aluminum building, and relates to the technical field of all-aluminum buildings. The water filtering wall body of the fabricated all-aluminum building comprises two sets of base plates which are symmetrically arranged, wherein connecting plates are arranged on the base plates, threaded nails are arranged on the connecting plates, an aluminum support is fixedly connected to the bottoms of the base plates, a composite plate mechanism and an adjusting mechanism are arranged on the aluminum support, an aluminum frame is arranged on the adjusting mechanism, one side of the aluminum frame is fixedly connected with a damp-proof gypsum board, and the composite plate mechanism is provided with a cushioning mechanism. The water filtering wall body is made of an aluminum material, the overall mass of the wall body is light, the wall body is more convenient to move, meanwhile, the water filtering wall body can be spliced and assembled in a simple clamping mode, a large amount of time does not need to be consumed in the assembling process, installation operation can be conducted by common workers, the installation cost is greatly reduced, the installation efficiency is remarkably improved, and the construction period is greatly shortened.