A polishing method can bring a polishing surface to the optimum condition for polishing, without using a dummy wafer or the like, before resuming polishing, thereby eliminating the cost of dummy wafer or the like. The polishing method comprises: carrying out a stand-by operation during a polishing-resting time period; carrying out a preparatory process to polishing, after completion of the stand-by operation, by dressing a polishing surface while supplying a polishing liquid to the polishing surface; and starting polishing of a workpiece after completion of the preparatory process to polishing. Determination as to whether to carry out the preparatory process to polishing after completion of the stand-by operation may be made based on the total operating time of the stand-by operation or the total effective number of the stand-by operations.