A device for coating a cylinder includes a coating head capable of being inserted into the cylinder, a plurality of coating guns which are provided on the coating head and are configured to discharge a coating material in a direction intersecting a longitudinal direction of the coating head, and a rotating cover which, when the coating material is discharged from one of a first coating gun and a second coating gun among the plurality of coating guns, is configured to cover the other of the first coating gun and the second coating gun, in which the plurality of coating guns are connected to coating material supply devices of different systems, respectively.