OBJECTIVE To determine the effect of intraocular lens (IOL) type and anterior capsulectomy technique on the incidence of posterior capsule opacification. METHODS Department of Ophthalmology, Medical Faculty, University of Ondokuz Mayis, Samsun, Turkey. METHODS Three hundred two eyes of 294 patients were examined retrospectively after IOL implantation in the capsular bag performed between February 1991 and November 1996. Patients were divided into 3 groups according to IOL type: poly(methyl methacrylate) (PMMA); heparin-surface-modified PMMA (HSM PMMA); plate-haptic silicone. Envelope capsulectomy or continuous curvilinear capsulorhexis (CCC) was used. Mean follow-up was 27 months (range 12 to 33 months). RESULTS Posterior capsule opacification developed in 47 cases (15.6%): 21.7% in the PMMA lens group after planned extracapsular cataract extraction (ECCE), 17.4% in the HSM PMMA lens group after planned ECCE, and 7.7% in the plate-haptic silicone lens group after phacoemulsification. Posterior capsule opacification occurred less in patients who had anterior capsulectomy using the CCC technique (11.5%) than in those having an envelope capsulectomy (24.5%) (P < .05). Posterior capsule opacification was significantly less in eyes with a capsular-bag-fixated plate-haptic silicone lens than in those with a PMMA or HSM PMMA IOL (P < .05). CONCLUSIONS This study demonstrated that the anterior capsulectomy technique and the IOL type influence the incidence of PCO.