The invention belongs to the field of tunnel construction, in particular to a spray dustfall device for the tunnel construction. The spray dustfall device for the tunnel construction can atomize a water source and at the same time enables the atomized water to be in fully contact with dust in the air. The spray dustfall device for the tunnel construction comprises a water storage frame, an installation box, wheels, an installation plate, a first fixed plate, a water outlet pipe, an external gear, a first rotating shaft, an atomization device, a fog outlet pipe, a fog spray frame, a first bearing seat, a first rack, a first sliding rail, a first sliding block, a sector gear, a first check valve, a connecting rod, a second rotating shaft, a first belt pulley, a first flat belt and the like.The wheels are fixedly connected to the bottom of the installation plate, and the water storage frame is fixedly connected to the top of the installation plate. The spray dustfall device for tunnel construction achieves the effects of atomizing the water source and at the same time enabling the atomized water to be in fully contact with the dust in the air.