The invention relates to a method and a device for characterizing a mask for microlithography. In a method according to the invention, structures of a mask intended for use in a lithography process in a microlithographic projection exposure apparatus are illuminated by an illumination optical unit, wherein the mask is imaged onto a detector unit by an imaging optical unit, wherein image data recorded by the detector unit are evaluated in an evaluation unit. In this case, for emulating an illumination setting predefined for the lithography process in the microlithographic projection exposure apparatus, the imaging of the mask onto the detector unit is carried out in a plurality of individual imagings which differ from one another with regard to the illumination setting set in the illumination optical unit or the polarization-influencing effect set in the imaging optical unit.