An insertion tool of an intraocular lens of novel structure in which the intraocular lens can be deformed into smaller one while rotation of the intraocular lens in an insertion tube is effectively prevented. Upper and lower flat planes (25, 26) are formed to spread flatly over an entire length of a through hole (22) in the insertion tube (20) and the upper and lower flat planes (25, 26) are connected smoothly with right and left wall faces (30, 28) over the entire length of the through hole (22). At at least a part of the through hole (22) in an extending direction thereof, the right and left wall faces (30, 28) have longitudinal linear portions extending substantially in parallel in a vertical direction on a proximal end opening (23) side. On the other hand, with its radius of curvature decreasing gradually in a covered shape which becomes inwardly concave as it approaches a distal end opening (24), the upper flat plane (25) is allowed to gradually approach the lower flat plane (26), and a tapered portion having a reduced cross-sectional area is formed, thus obtaining the distal end opening of substantially oval shape.
