Crankcase ventilation system for a supercharged combustion engine

Crankcase ventilation for an internal combustion engine with exhaust gas turbocharging comprises a first ventilation line (30) connected at one end to the crankcase housing chamber and at the other end to an intake pipe (10) of the engine, and a second ventilation line (40) connected at one end to the crankcase housing chamber and at the other end to the intake side of a compressor (waste gas turbocharger) (14). A non-return valve (34) arranged in the first ventilation line prevents in supercharging operation the overpressure in the intake pipe from entering the crankcase housing chamber. A non-return valve (42) is arranged in the second ventilation line. The low-pressure level in each ventilation line is adjusted via a common pressure regulator (38). Preferred Features: The pressure regulator is arranged on a ventilation line section (32) provided for both ventilation lines. An oil separator (36) located upstream of the pressure regulator is provided in the ventilation section.