A machine for cleaning and polishing grains comprises at least one treatment chamber which includes an upper frusto conical baffle having a central opening to admit grains thereinto, an intermediate rotatory disc to impart movement to the grains falling thereon through said opening and a lower frusto conical baffle having a central opening to discharge the grains, said upper frusto conical baffle having a stationary brush and a stationary set of flexible fingers vertically hanging therefrom, and said rotatory disc having a rotatory brush and a rotatory set of flexible fingers hanging from its lower surface in a direction and to a distance suitable to confront the upper surface of said lower frusto conical baffle, whereby the grains are cleaned by the action of said stationary brush and set of fingers on the moving grains driven by the rotatory disc, and by the action of said rotatory brush and set of fingers on the grains sliding down said lower frusto conical baffle.