The polishing apparatus (100) comprises a turn table (10), which polishes a semiconductor wafer (2), and a holding and pressing part (20), which holds and presses the semiconductor wafer (2) against a polishing surface (12a) of the turn table (10). The holding and pressing part (20) transmits a force from an air bag (62) to the semiconductor wafer (2) via a pressurized fluid layer (L) to thereby press the semiconductor wafer (2) against the polishing surface (12a) via the pressurized fluid layer (L), so that the semiconductor wafer (2) can be polished. Thereby, it is possible to uniformly polish the semiconductor wafer (2).