The road milling machine according to the invention comprises a cleaning device which has a cleaning unit arranged in front of the work roller in the working direction. The cleaning unit ensures that the surface of the terrain over which the wheels or running gears travel is clear of material. As a result, an optimum milling result is always achieved. The invention takes effect in particular when using small millers which have at least one rear wheel or running gear which can be moved into an inner working position in relation to a longitudinal side of the machine frame and into an outer working position in relation to a longitudinal side of the machine frame. In this preferred embodiment, the cleaning device comprises a pivot device which is designed in such a way that the cleaning unit can be moved into an inner working position in relation to a longitudinal side of the machine frame and into an outer working position in relation to a longitudinal side of the machine frame. In the inner or outer working position, the cleaning unit is arranged on the same track as the rear wheel or running gear which can be moved into the inner or outer working position. This ensures that the track of the rear wheel or running gear is clear of milled material or other dirt, wherein the cleaning unit does not protrude too far beyond the rear wheel or running gear.