To reduce a noise level around a car washing place by preventing the radiation of noise generated outside from an air nozzle for drying in a drying process while washing a car.

In this sound-proof device for a car washer 10 equipped with an air nozzle 15 for drying in a car washing room 13 having an entrance/exit of a vehicle 1, front and rear sound-proof curtains 21, 22 holding the air nozzle 15 for drying from front and rear sides thereof are installed on the ceiling side in the car washing room 13, the sound-proof curtains 21, 22 are elevated and lowered to the upper face of the vehicle in the drying process while washing the car, and the noise generated by the air nozzle 15 for drying is blocked from the outside by the sound-proof curtains 21, 22.