Abstract: A method for staining and destaining a gel, including: a staining step of staining the gel using an acid aqueous solution that contains a dye and does not contain alcohol; and a destaining step of destaining the dye by electrophoresis by applying a voltage to the gel disposed in an acid aqueous solution that does not contain alcohol. The destaining step can be conducted by using, for example, an electrophoresis destaining device including: a body vessel; a pair of electrodes; and a gel container, wherein the pair of the electrodes and the gel container disposed between the electrodes are arranged in parallel to each other in the body vessel along a spacer of the body vessel.