Screw compressor

A screw compressor comprising:

• a screw rotor including a rotor lobe section that has a twisted lobe and also has a discharge-side end face on one side in an axial direction, and a discharge-side shaft section provided on the one side in the axial direction at the rotor lobe section;
• and
• a discharge-side bearing mounted on the discharge-side shaft section, wherein
• the screw rotor has a cooling flow path extending in the axial direction at least inside the discharge-side shaft section,
• a groove structure is provided at at least a part of a region on a wall surface of the cooling flow path, the region being between a position of the discharge-side end face in the axial direction and a mounting position of the discharge-side bearing,
• the groove structure includes grooves or a groove that has a lengthwise component in a circumferential direction of the screw rotor and that is spaced apart in the axial direction,
• a nozzle that is a stationary member for supplying a coolant is arranged inside the cooling flow path with a gap between the nozzle and the wall surface, and
• the nozzle is arranged in such a manner as to overlap at least a part of the groove structure in the axial direction.