A rotary compressor, including a cylinder, an inner peripheral surface of which is defines a compression space, provided with a suction port configured to communicate with the compression space to suction and provide refrigerant to the compression space; a roller rotatably provided in the compression space of the cylinder, and including with a plurality of vane slots at predetermined intervals along an outer peripheral surface, the plurality of vanes each providing a back pressure at one side thereinside; a plurality of vanes slidably inserted into the plurality of vane slots, respectively, to rotate together with the roller, front end surfaces of the plurality of vanes coming into contact with an inner periphery of the cylinder due to the back pressure to partition the compression space into a plurality of compression chambers; and a main bearing and a sub bearing provided at both ends of the cylinder, respectively.