The present invention relates to a device for cleaning door and window roller blinds which allows cleaning by brushing both the outer and the inner part by simply raising and/or lowering the same and which basically comprises two brushes, one outer brush (2) coupled in the upper part of the window frame (4) and another inner (3) which is fixed close to the lower groove of the box (9) of the drum (10) through which the blind (1) exits, wherein said brushes have a length approximately equal to the width of the blind (1) and are placed such that the bristles of both come into contact with and brush against the outer and inner surface of the blind (1) cleaning it.