To provide an exposure processor which can increase the positioning precision of a stage for exposed object setting by preventing the stage from being influenced largely by the expanding/contracting force of bellows.

This processor is equipped with a processing tank 2, a stage 3 for exposure object setting which is arranged in the processing tank 2, a stage moving means M2 which moves the stage 3 in a fixed direction, a drawing-in opening 21 for drawing a connection member 70 connected to the stage 3 into the processing tank 2 from outside, and a 1st expansible/shrinkable bellows which seals the drawing-in opening 21. Further, the processor is equipped with a moving body 4 for assistance which can be freely moved in the fixed direction in the processing tank 2 by a moving means other than the stage moving means M2 and bears force produced as the 1st bellows extends and shrinks.