PURPOSE: To accurately and easily measure the fine structure of an intracorporeal mucous membrane, by constituting the biopsy measure grasped by a biopsy forceps at the leading end thereof in a detachable manner by laminating two lusterless translucent ultrathin materials and providing a scale to the laminated part of both of them.

CONSTITUTION: A biopsy measure is constituted by preliminarily applying a scale 62 to the surface of one ultrathin material 61a by printing and laminating the other ultrathin material 61b to the printed surface thereof. The dimension of the biopsy measure is below 1mm in a width and below 20mm in a length and graduations are provided at a 0.2mm-interval within a range of about 10mm. In actually measuring the lesion part generated in an intracorporeal mucous membrane, the grip part 63 of the biopsy measure 6 is grasped by a biopsy forceps 7 at the leading end thereof and inserted in an endoscope 1 from the forceps port 51 thereof to be allowed to reach the intracorporeal mucous membrane 8 from the forceps outlet 21 to be adhered to the lesion part 81. By observing this state under the illumination from an optical fiber, the dimension of the lesion part 81 can be accurately read.