The invention relates to a separator for crank housing ventilation of an internal combustion engine. The separator comprises at least one vortex chamber (2) extending along a longitudinal axis (3), wherein the vortex chamber (2) comprises an inlet for a ventilation stream (6), in particular a tangential inlet, relative to the longitudinal axis (3) at an end (4) on the inlet side. The vortex chamber (2) further comprises a common outlet (8) for the ventilation stream (6) and for oil entrained along with the ventilation stream (6), said common outlet being located at the end on the outlet side of the vortex chamber opposite the end (4) on the inlet side, relative to the longitudinal axis (3). The vortex chamber (2) is enclosed in the outlet (8) area thereof by an impact absorber (9) comprising an impact base (10) and a peripheral wall (11), wherein the impact base (10) covers the outlet (8) at a distance therefrom.