The invention relates to an oil separator for the separation of oil from the crankcase ventilation gas of an internal combustion engine, comprising a housing wherein a separating element is arranged, comprising an inlet for gas to be cleaned, an outlet for cleaned gas and an outlet for separated oil. The novel oil separator is characterized by a crude gas area of the housing adjacent to the inlet and provided with an oil sink wherein coarse oil carried by the incoming gas flow is deposited; also characterized in that the oil separator comprises, in addition to the separating element, a coarse oil cyclone whose inflow opening is located at the same level as the oil sink therein, and in that the separating element has an inflow opening which is spatially located above the inflow opening of the coarse oil cyclone.