The invention discloses an fabricated wallboard with gap sealing and 
water leakage preventing functions, and belongs to the technical field of fabricated wallboards. The wallboard comprises a first fabricated wallboard, a second fabricated wallboard, a third fabricated wallboard, an 
extrusion outer plate, a sealing air bag, an inflating bag and a wallboard base material; and the third fabricated wallboard is fixedly mounted on the outer wall of one side of the second fabricated wallboard. According to the fabricated wallboard with the gap sealing and 
water leakage preventing functions, by arranging the inflating bag, when the wallboard is assembled at ordinary times, the inflating bag can be extruded by the 
extrusion outer plate of the external 
assembly wallboard, internal air can be transmitted into a sealing air bag through an air guide 
pipe, and the sealing air bag expands to be attached to the outer top of a sealing 
gasket. The expanded sealing air bag and the attached sealing 
gasket can effectively fill the 
assembly gap of the fabricated wallboard, external water spots can be effectively prevented from seeping into the fabricated wallboard through the 
assembly gap, a traditional simple sealing waterproof design of a sealing rubber strip is abandoned, the sealing air bag and the attached sealing 
gasket can continuously keep the sealing effect, and the situation that the sealing performance is reduced is avoided.