A balloon coating method is disclosed for forming a coating layer on an outer surface of a balloon of a balloon catheter. The method includes an application step where a vertically extending dispensing tube for supplying a coating solution containing the water-insoluble drug and a solvent is formed at its end portion with an opening portion for discharging the coating solution therethrough and when an opening portion-formed end portion side of the dispensing tube is kept in contact with the outer surface of the balloon in such a manner as to be oriented to a rotating direction of the balloon while the balloon is rotated about an axis of the balloon, the coating solution is discharged through the opening portion and applied to the outer surface of the balloon while the dispensing tube is moved relative to the balloon in an axial direction of the balloon.