A variable capacity rotary compressor to prevent eccentric bushes from rotating faster than a rotating shaft, and includes upper and lower compression chambers having different interior capacities thereof, and the rotating shaft with upper and lower eccentric cams being provided thereon to be eccentric from the rotating shaft in a common direction. Upper and lower eccentric bushes are fitted over the upper and lower eccentric cams, respectively, with a slot provided there between. A locking pin changes a position of the upper or lower eccentric bush to a maximum eccentric position. Upper and lower brake units are, respectively, provided between the upper eccentric cam and the upper eccentric bush, and between the lower eccentric cam and the lower eccentric bush. The upper and lower brake units, respectively, include first and second upper brake balls, and first and second lower brake balls, to restrain the upper and lower eccentric bushes.