The utility model discloses a novel compound dust collecting box, relating to a collecting device for viscous dust containing water vapor. The novel compound dust collecting box consists of an upper box body and a lower box body, wherein the upper box body is provided with three choke plates for filtering; a square air outlet is just formed in the upper side of the left side surface of the box body and positioned above the choke plates; a circular air inlet is just formed in the back surface of the lower box body and is butted with a horizontal air exhaust pipe in an equal altitude manner; a square cleaning hole is just formed in front of the lower box body, and a cover plate is connected to the cleaning hole by a hinge. The novel compound dust collecting box is simple in structure and capable of effectively collecting dust and reducing pollution of dust and waste gas to plants and atmosphere, so that the dust content of discharged waste gas accords with the emission standards in China.