To prevent a cleaning liquid, etc., from scattering around by blocking a gap to a floor surface when a whole brush drive mechanism is inclined with the traveling movement of a floor polishing machine.

A scatter preventing cover 20 in a drooping state for surrounding the circumference of a brush 4 in a brush cover 5 is arranged and connected to a supporting cover 11 for covering the brush cover 5 of the brush drive mechanism 2 in a floor polishing machine main body 1 from above. The supporting cover 11 is formed of a soft and elastic material so that the peripheral edge of the supporting cover 11 can bend. The lower edge of the scatter preventing cover 20 is in contact with the floor surface at all times even when the brush drive mechanism 2 is inclined or rocked to prevent the occurrence of the gap between the lower edge of the brush cover 5 and the floor surface and prevent the cleaning liquid, etc., from scattering to the periphery due to the rotating brush 4.