The present invention provides an EUV mask blank in which the thickness of the absorbing layer is optimized, whereby the thickness of the absorption layer can be reduced in comparison with conventional thickness in a range that does not affect pattern characteristics. A reflective mask blank for EUV lithography in which a reflective layer for reflecting EUV light and a absorbing layer for absorbing EUV light are formed in the stated order, the reflective mask blank for EUV lithography characterized in that the thickness of the absorbing layer is set so as to be within a range of ±2.0% of minimum thickness and so that the average beam reflectivity is 4.0% or less in a wavelength region of 13.3 to 13.7 nm.
