The invention relates to a method for analyzing a defect of a photolithographic mask for an extreme ultraviolet (EUV) wavelength range (EUV mask) comprising the steps of: (a) generating at least one focus stack relating to the defect using an EUV mask inspection tool, (b) determining a surface configuration of the EUV mask at a position of the defect, (c) providing model structures having the determined surface configuration which have different phase errors and generating the respective focus stacks, and (d) determining a three dimensional error structure of the EUV mask defect by comparing the at least one generated focus stack of the defect and the generated focus stacks of the model structures.