According to an aspect of the present invention, there is provided a pattern structure inspection method including irradiating a wave from a wave source onto a sample including a pattern region in which a structure having a certain pattern is provided on a substrate, collecting speckle data generated due to multiple scattering of the wave in the pattern region, by using a data collector, and analyzing whether the structure of the pattern region has a defect, by comparing the collected speckle data to reference speckle data.