PURPOSE: To enhance the working efficiency of cutting of optical fibers, by smoothly cutting the optical fibers, successively at positions to be cut, which optical fibers are held between securing members, being spaced from each other, with the use of a circular rotary grindstone, and by simultaneously polishing the cut end faces of the optical fibers with the use of the side surface of the grindstone.

CONSTITUTION: A very thin circular plate-like grindstone 13 which is rotated at a high speed is relatively advanced in the direction orthogonal to the axes of a plurality of optical fibers 2 which are held in protecting grooves 11a, 12a which are formed in upper and lower securing beds 11, 12, being spaced at predetermined intervals from each other, and therefore which are successively cut with the use of the peripheral part of the grindstone, and simultaneously, the cut end faces of the optical fibers 2 are polished by the side surface of the grindstone so that the end faces are smoothly finished.