The invention discloses a combined screening and dedusting device for building yellow sand, which comprises a housing, a circulating air pump, an exhaust hose, a filter box and an intake hose, and the housing is provided with an upper cover and a feeding hopper , material guide plate, sieve plate, right air port, left air port and discharge port; the lower end of the shell is provided with a threaded column, a rotating placement plate, a circulating air pump, an exhaust hose, a filter box and a connecting air pipe; the filter box There are movable upper cover, filter cloth plate and intake hose on the top; threaded joints are provided at the end of the exhaust hose and intake hose; fixed plates, rotating shafts, support frames, bottom plates, and swing screw rods are installed on both sides of the housing , Counterweight slider and fastening bolts. The invention cooperates with the threaded joint at the end of the exhaust hose and the intake hose, and the left air port and the right air port, which can promote the passage of materials and synchronously remove dust under the action of the circulating air pump. Impurities can also be recovered after the screening is completed. , easy to use and efficient, can improve processing efficiency.