Abstract: Disclosed is an thickness measuring apparatus comprising: a C-shaped block; a pair of arms which arc provided on the block, each of which is equipped with a pivot section situated at one end thereof, each pivot section being equipped with a spring element; a pair of lever members pivotably mounted on the respective spring elements; measuring elements mounted on the respective outer end sections of the lever members and adapted to be brought into contact with the article to be measured; a first compression spring provided between one of the pair of arms and a section of one of the lever members which is near the inner end thereof so as to bias this lever member; a second compression spring provided between the other of the pair of arms and a section of the other of the lever members which is near the inner end thereof so as to bias this lever member; thickness measuring devices provided respectively on the pair of arms and adapted to detect any movement of the lever members so as to measure the thickness of th