An evaluation apparatus which evaluates a sample having a porous layer. The apparatus includes a light source which irradiates the sample with light, an imaging spectrometer which spectroscopically measures light reflected by the sample and senses an image, a first calculator which obtains amplitude information on an amplitude of a spectral reflectance of the sample based on the image sensed by the imaging spectrometer, a memory which holds in advance relationship information representing a relationship between amplitude information of spectral reflectance of a member having a porous layer and an absorption coefficient of the porous layer of the member, and a second calculator which obtains an absorption coefficient of the sample based on the amplitude information obtained by the first calculator and the relationship information held in the memory.