Apparatus for separating oil from crankcase ventilation gases of an internal combustion engine having at least two oil separators in the form of cyclones connected in parallel and traversed by the crankcase ventilation gases. The apparatus is equipped with a control valve that divides the volumetric flow of the crankcase ventilation gases into at least two subflows, depending on the magnitude of the volumetric flow, and conducts the subflows to the at least two oil separators. A control piston releases or blocks access of the gases to additional cyclones depending on the dynamic pressure of the crankcase gas.