To compare intraocular lens (IOL) decentration between patients in whom the continuous curvilinear capsulorhexis (CCC) completely covers the IOL optic and those in whom it incompletely covers the IOL optic and determine how an incompletely covered CCC affects the IOL position. A tertiary hospital in Japan. Single-center retrospective study. This study included 57 eyes of 57 patients (mean age 70.8±6.2 years) that underwent phacoemulsification and IOL (SN60WF; Alcon Laboratories, Fort Worth, TX) implantation in the bag between April 2010 and April 2015. The patients were classified based on whether the CCC completely (CC group) or incompletely (NCC group) covered the IOL optic using an anterior eye segment analysis system (EAS-1000; NIDEK, Gamagori, Japan). The IOL decentration of the groups was analyzed using EAS-1000 at 1 week, 1 month, 3 months, and 6 months postoperatively and compared. The relationship between the NCC location and IOL direction at 3 months postoperatively was analyzed. The NCC group (25 eyes) had a significantly higher amount of IOL decentration than the CC group (32 eyes) at 1 week, 1 month, 3 months, and 6 months postoperatively (P < .05). There was a correlation between the direction of IOL decentration and NCC location, and IOL decentration in the NCC group occurred in the opposite direction to the NCC area. An anterior capsule opening that completely covers the IOL optic is important to control IOL decentration.