AIM: To quantify intraoperative and postoperative complications in complex phacoemulsification cataract extraction (phacoemulsification) with iris manipulation compared to non-complex and complex phacoemulsification without iris manipulation. METHODS: All phacoemulsification cases at the University of Colorado between January 1, 2014, and June 30, 2017 were included. Exclusion criteria for the primary outcome of intraoperative complications were planned combination surgery and eyes with less than 28d follow-up. Exclusion criteria for the secondary outcomes of postoperative complications were unplanned additional surgery, and chronic steroid eye drop use prior to surgery. Data including sex, race/ethnicity, surgery length, visual acuity, intraoperative and postoperative complications, and intraocular pressures (IOP) were collected and analyzed utilizing general linear and Logistic regression modeling. RESULTS: The medical records of 5772 eyes were reviewed (500 complex without iris manipulation, 367 with iris manipulation). The number of any intraoperative complication in the complex with iris manipulation and complex without iris manipulation groups was 15 (4.1%) and 26 (5.2%), respectively, compared to 41 (0.8%) in the non-complex group. Postoperative inflammation was found in 135 (2.8%) non-complex cases, 20 (4.1%) complex cases without iris manipulation, and 20 (5.6%) complex cases with iris manipulation. The adjusted odds ratio of postoperative inflammation in phacoemulsification with iris manipulation compared to non-complex was 2.3 (95%CI: 1.3-4.0, P=0.005). The rate of IOP spikes >10 mm Hg was significantly greater in cases with iris manipulation (P=0.001). CONCLUSION: Complex cases have more intraoperative complications. However, only complex cases with iris manipulation led to increase rates of postoperative inflammation and IOP spikes >10 mm Hg.