A material property inspection apparatus includes a conveyance unit, a light source, an irradiation unit, a light receiving unit, a signal detection unit, a material property value input unit, an inspection set value input unit, and a processing unit. The processing unit calculates a relation equation between the material property value from the material property values of the plurality of test pieces and the light intensity of the transmitted light or the reflected light of respective test pieces, calculates the material property value of the inspected object from the light intensity of the transmitted light or the reflected light detected by the signal detection unit and the relation equation, compares the calculated material property value of the inspected object with the inspection set value inputted from the inspection set value input unit, and determines the quality of the inspected object.