Background: phacoemulsification can cause changes in the anterior segment parameters that could be detected by anterior segment optical coherence tomography. Purpose: To determine the changes in the anterior segment parameters and intraocular pressure after phacoemulsification (IOP). Subjects and methods: A prospective, non-randomized study included twenty eyes with visually significant cataract that underwent phacoemulsification with foldable intraocular lens implantation (IOL). Complete ophthalmological examination and anterior segment optical coherence tomography (ASOCT) were performed before surgery and one month postoperatively. Results: There were statistically significant differences in the anterior segment parameters after cataract surgery. The anterior chamber angle (ACA) at the temporal side before and one month after surgery were 22.58º ± 6.4º , 33.14 º ± 6.48º respectively (p < 0.001). The ACA at the nasal side before and one month after surgery were 23.33º ± 6.93º, 34.16º ± 6.99º respectively (P< 0.001). Conclusion: Phacoemulsification with IOL implantation results in significant widening of the ACA proved by quantitative assessment of ASOCT imaging. At the same time it caused small but significant reduction in IOP.