OBJECTIVE To examine anterior chamber depth (ACD) and anterior chamber angle (ACA) in patients with glaucoma after cataract extraction with an anterior optical coherence tomography (OCT) system. METHODS A new commercially available 1310 nm infrared light anterior segment OCT system was used for anterior chamber evaluation. Sixty patients (n=20 with primary open angle glaucoma [POAG], n=20 with angle closure glaucoma [ACG], and n=20 with no known glaucoma as control group) with a mean age of 68.8+/-13.9 years undergoing cataract surgery were enrolled. RESULTS Before cataract surgery, ACD and ACA of the ACG group were significantly lower compared to the POAG and control groups (ACD p<0.005; ACA p<0.005). After cataract extraction, ACD and ACA increased significantly in the ACG group (3.1+/-0.4 mm vs 1.8+/-0.2 mm, p<0.005 and 32.3 degrees +/-7.7 degrees vs 16.0 degrees +/-4.7 degrees , p<0.005). In the POAG and control groups, ACD and ACA also increased postoperatively, but not as much as in the ACG group. After cataract extraction, IOP decreased significantly in the glaucoma groups (ACG: 15.6+/-6.1 vs 18.6+/-5.7 mm Hg, p=0.008; POAG: 16.2+/-3.4 vs 20.7+/-8.0 mmHg, p=0.02) and was almost the same in all three groups after surgery (control group after surgery: 15.2+/-2.8 mmHg). CONCLUSIONS Both ACD and ACA increased significantly after cataract extraction and IOL implantation. IOP reduction after surgery was higher in the glaucoma groups compared to the control group.