PURPOSE: To enable cleansing of the end face and the rear of a substrate concurrently by a method wherein a roller-type horizontal rotating brush with dips cleansing liquid up, a vertical rotating brush which is in contact with the upper end of the horizontal brush and dips cleansing liquid, a substrate conveying means, and an air jetting means which spouts air slantingly downward from the inside of the vertical rotating brush are provided all together.

CONSTITUTION: A roller-type horizontal rotating brush 3 dips cleansing solution 2 up from a tank 1 as it rotates and furthermore the cleansing solution is made to be dipped up with vertical rotating brushes 11. A substrate 20 is cleansed while it is horizontally conveyed in such a manner that its rear is cleansed with the roller-type rotating brush 3 and both its end faces are cleansed with the vertical rotating brushes 11 in cooperation with the roller-type rotating brush 3. Cleansing solution stagnant near the end face of the substrate 20 upper face is made dispersed off the substrate 20 by compressed air jetted from a pipe 18 provided inside at an upper position. In this structure, the side face and the rear of a substrate can be effectively cleansed without making cleansing solution permeate into a component mounting section provided on a substrate surface.