There is described a method which enables stable manufacture of a high-quality, ultra-thin epitaxial silicon wafer, as well as an epitaxial silicon wafer capable of bearing shipment manufactured by the method. A method of manufacturing an epitaxial silicon wafer having an ultra-thin epitaxial film, by means of forming an epitaxial film on a silicon wafer after having annealed the silicon wafer, includes the steps of: sufficiently smoothing COPs formed in the surface of the silicon wafer by means of appropriately setting annealing conditions according to an size of COPs in the vicinity of a surface of the silicon wafer; and forming an epitaxial film through epitaxial growth.