A substrate polishing apparatus includes: a polishing table supporting a polishing pad; a top ring configured to press the substrate against the polishing pad; and a pad temperature regulator configured to regulate a surface temperature of the polishing pad. The pad temperature regulator includes a pad contact element and a liquid supply system configured to supply a temperature-controlled liquid to the pad contact element. The pad contact element has a space therein and a partition that divide the space into a first liquid passage and a second liquid passage that are connected in series. At least one baffle substantially perpendicular to a radial direction of the polishing table is provided in each of the first liquid passage and the second liquid passage.
