PURPOSE: To compare the astigmatism-reducing effect of an aspheric toric intraocular lens (IOL) and an aspheric nontoric IOL with an opposite clear corneal incision (OCCI) in cataract surgery. SETTING: Vienna Institute for Research in Ocular Surgery, Hanusch Hospital, Vienna, Austria. DESIGN: Prospective randomized clinical study. METHODS: Patients with low to moderate corneal astigmatism scheduled for cataract surgery received an aspheric toric IOL (Lentis L-312T) or an aspheric nontoric IOL (Lentis L-312) combined with an OCCI. Keratometry and corneal tomography were performed 1 hour, 1 week, 3 months and 9 months postoperatively. Postoperative residual astigmatism was measured using an autorefractor. Rotational toric IOL stability was analyzed using retroillumination photography. RESULTS: Fifty-five patients were included. Three months postoperatively, the mean reduction in corneal astigmatism was 0.67 diopter (D) +/- 0.58 (SD) in the toric group and 0.18 +/- 0.52 D in the nontoric OCCI group. The mean uncorrected distance visual acuity was 0.29 +/- 0.30 logMAR and 0.09 +/- 0.18 logMAR, respectively (P=.02). The mean refractive astigmatism was 1.02 +/- 0.54 D and 0.68 +/- 0.52 D, respectively (P=.05). One hour, 3 months, and 9 months postoperatively, the mean absolute IOL misalignment of toric IOLs was 4.99 +/- 4.66 degrees, 13.59 +/- 11.29 degrees, and 19.90 +/- 14.48 degrees, respectively. CONCLUSIONS: The toric IOL tended to rotate significantly postoperatively. Visual acuity was good in both groups. Residual refractive cylinder was significantly lower in the toric IOL group.