The present disclosure provides a substance identification device and a substance identification method. The substance identification device comprises: a classifier establishing unit configured to establish a classifier based on scattering density values reconstructed for a plurality of known sample materials, wherein the classifier comprises a plurality of feature regions corresponding to a plurality of characteristic parameters for the plurality of known sample materials, respectively; and an identification unit for a material to be tested, configured to match the characteristic parameter of the material to be tested with the classifier, and to identify a type of the material to be tested by obtaining a feature region corresponding to the characteristic parameter of the material to be tested.