The present invention provides a method for polishing a wafer including, after unloading and before loading to hold a next wafer to be polished: measurement to measure a depth PDt of a concave portion of a template after taking out a polished wafer; calculation to calculate a difference ΔPD between the measured depth PDt of the concave portion and a depth PD0 of the concave portion of the template before being used for polishing; and adjustment to adjust polishing conditions for a next wafer to be polished in accordance with the calculated difference ΔPD. Consequently, there are provided the method for polishing a wafer and a polishing apparatus which enable adjusting a fluctuation in flatness of each wafer caused due to a fluctuation in numerical value of a pocket depth of a template.