An intraocular-lens insertion device is adapted to deform a deformable intraocular lens into a smaller size and insert the intraocular lens into an eye via an insertion tube. An intraocular-lens guide is provided on the inner surface of the insertion tube. The guide may be a rail-shaped projection or a groove, which extends parallel to a direction along which the intraocular lens is pushed out. A stress release structure is provided on the insertion tube in order to release stress of the intraocular lens produced due to deformation thereof. Moreover, a frictional-resistance increasing structure is provided on the inner surface of the insertion tube to be located in the vicinity of the stress release structure. The frictional-resistance increasing structure increases frictional resistance between the inner surface of the insertion tube and the intraocular lens. The frictional-resistance increasing structure may be a roughened surface which completely or partially covers the inner surface of the insertion tube.