Abstract: A rotary screw compressor that includes a male rotor and a female rotor cooperating together within a casing. The casing has a discharge outlet connected to an outlet port at a high pressure end of the working space and a suction inlet at the low pressure end of a working space. The rotor is rotatably supported at one end thereof through a bearing arrangement that includes a bracket fixed to an end cover. The bearing bracket projects into an axial cavity provided in the rotor to form a first chamber between the bracket and the rotor. The bracket is provided with an oil feed channel to feed oil into the first chamber. The rotor is rotatably supported at the low pressure end thereof through the bearing arrangement. The corresponding bearing bracket is mounted at the low pressure end of the working space and the outer circumferential surface thereof is provided with at least a groove connected to the oil feed channel and a recess connected to an oil drainage channel provided in the bearing bracket.