A polishing apparatus is configured to simultaneously polish both surfaces of a work, and includes a pair of stools rotating in opposite directions, a pair of detecting units configured to detect rotation rates of the stools, a pressurizing unit configured to compress the work between the pair of the stools, a slurry supply unit configured to supply a slurry to the stool, and a control unit configured to reduce, when determining that a frictional force between the polishing surface and the work exceeds a threshold, at least one of a load applied by the pressurizing unit, the rotation rate of the stool, and a supply amount of the slurry supplied by the slurry supply unit.