An intraocular lens insertion device having a configuration in such a manner that, with the displacement of a haptic toward the convex side of an optical portion, which can be deformed in a curved shape, restricted by an engaging part provided to the tip part of a plunger, the haptic is deformed in a curved shape in the direction in which the haptic approaches the optical portion. The configuration allows, when the intraocular lens is pushed out by the plunger, the haptic to enter a gap formed on the concave side of the optical portion which has been deformed in a curved shape.