The utility model discloses a case roof beam automatic spray device. It is including setting up the track in the precast box girder side, can be quick -witted at the case roof beam automatic spray that the track went upward away, traveling system is drawn together to case roof beam automatic spray press packed bale, spraying system, water system in the automation, be used for controlling traveling system, spraying system, the control box of water system in the automation, traveling system includes the frame, the setting is at the walking wheel of frame bottom, the actuating mechanism of drive walking wheel walking, spraying system includes the water storage box, the immersible pump of setting in the water storage box, the shower of being connected with the immersible pump, the fixed upper portion that sets up at the frame of water storage box, the shower includes the shower A and an at least shower B of an at least vertical setting, shower A's top is connected with the universal nozzle that can spray to the flat face of case back, shower B is the arc structure of downwarping, be provided with a plurality of atomizer on the shower B, the water system is including setting up the cable floating ball liquid level switch in the water storage box in the automation.