A variable capacity rotary compressor is designed to make a pressure of a high-pressure side be uniformly applied to upper and lower ends of a roller of a low-pressure side, allowing the roller of the low-pressure side to be smoothly rotated. The compressor includes a housing to define two compression chambers which are partitioned by a partition plate. Two flanges are mounted to predetermined positions of the compression chambers to close openings of the compression chambers. A rotating shaft passes through the compression chambers and the partition plate. Two eccentric units are mounted to the rotating shaft to be placed in the compression chambers. One of the eccentric units is eccentric from the rotating shaft to execute a compression operation while a remaining one of the eccentric units is released from eccentricity from the rotating shaft to execute an idle rotation, according to a rotating direction of the rotating shaft. Two rollers are fitted over the eccentric units, with inside portions of ends of the rollers being spaced apart from inside surfaces of the flanges, offsetting pressure applied to the ends of the rollers.