In a rotary atomizer (10) including a rotating bell (92) secured to a rotating shaft (20a) of an air motor (20) held in an atomizer body, the rotating bell having a plurality of orifices (92a) for supplying paint to an object to be painted, the rotating bell being rotated to spray the paint toward the object to be painted, the rotary atomizer comprises a paint passage (102a) with a paint port (112c) at an end thereof fluidly communicating with the orifices of the rotating bell, and a water passage (108) arranged outside of the paint passage and having a water port at an end of the water passage leading to the orifices of the rotating bell. A needle (94) for opening and closing the paint port may be provided.