It is an object to provide an epitaxial silicon wafer that is provided with an excellent gettering ability in which a polysilicon layer is formed on the rear face side of a silicon crystal substrate into which phosphorus (P) and germanium (Ge) have been doped. A PBS forming step for growing a polysilicon layer is executed on the rear face side of a silicon crystal substrate into which phosphorus and germanium have been doped at a high concentration to execute a baking treatment. After a surface layer of the silicon crystal substrate is then polished up to a predetermined amount, a silicon epitaxial layer is grown by a CVD method. By the above steps, the number of LPDs (caused by an SF) that occur on the surface of the epitaxial silicon wafer due to the SF can be greatly reduced.