PROBLEM TO BE SOLVED: To provide an intraocular lense inserting instrument with a novel structure which enables the smaller deformation of intraocular lenses while effectively preventing the rotation of the intraocular lenses within an inserting cylinder part.SOLUTION: Upper and lower flat surfaces 25 and 26 are formed extending flatly over the entire length of a through hole 22 in an inserting cylinder part 20 while being connected smoothly to left and right wall surfaces 28 and 30 over the entire length of the through hole 22. The left and right wall surfaces 28 and 30 have vertical linear parts extending almost parallel in the vertical way on the side of the base end opening part 23 at least at a part in the direction of the extension of the through hole 22. A tapered part which is made curved to be concave inward gradually toward the tip opening part 24 with a gradual reduction in the radius of curvature so that the upper and lower flat surfaces 25 and 26 approach each other gradually to lessen the sectional area of the inserting cylinder part is formed to make the tip opening part 24 almost oval.COPYRIGHT: (C)2008,JPO&INPIT