A rotary compressor is provided that may include a rotational shaft including at least one protrusion formed on an outer peripheral surface, first and second bearings configured to support the rotational shaft in a radial direction, a cylinder disposed between the first and second bearings to form a compression space, a rotor disposed in the compression space and coupled to the rotational shaft to compress a refrigerant as the rotor rotates, and at least one vane slidably inserted into the rotor, the at least one vane coming into contact with an inner peripheral surface of the cylinder to separate the compression space into a plurality of regions. The rotor may include at least one groove which is formed on an inner peripheral surface and faces the at least one protrusion.