A substrate holder capable of preventing an increase in a polishing rate of an edge portion of a substrate, even when polishing a plurality of substrates successively, is disclosed. The substrate holder includes: a top ring body configured to hold the substrate; and a retaining ring disposed so as to surround the substrate held by the top ring body. The retaining ring includes a pad pressing structure in an annular shape which is to be brought into contact with the polishing pad, and the pad pressing structure has a width in a range of 3 mm to 7.5 mm.