PROBLEM TO BE SOLVED: To provide a low-cost light guide suitable to be used for an endoscope.SOLUTION: This optical fiber structure 2 is formed by arranging, inside a tubular resin body 9, a plurality of bare optical fibers 10 along the long direction X of the resin body 9 in the circumferential direction. A linear cut split 11 nearly parallel to the bare optical fibers 10 reaching a lumen 2b from the outer circumferential face 9a of the resin body 9 is cut in an intermediate position in the long direction X of the resin body 9.
