Grinder-doser device for coffee beans includes a body which internally houses an electric motor, having a shaft, which is integral in rotation with the lower grinder holder to which the lower grinder is joined, said lower grinder holder, and said lower grinder being housed inside a head which has a horizontal annular seat in the lateral edge, which houses an upper grinder. The upper grinder being formed by a toothed annular portion housed inside a hollow annular portion, which in turn is surrounded by an annular portion, which rests on the annular seat. The flat upper surface of the upper grinder is rectified and collimated with the plane passing through the ends of the teeth of the toothed portion.