OBJECTIVE To examine intraocular pressure (IOP) changes in primary and upward gazes before and after orbital decompression in patients with thyroid eye disease. METHODS Seventy-eight orbits of 40 patients who underwent orbital decompression between June 2010 and September 2012 were retrospectively reviewed. Subjects were divided in 2 groups according to the number of orbital walls removed: deep lateral orbital wall decompression group (Group A) or balanced decompression group (Group B). IOP was measured using Goldmann applanation tonometry in primary gaze and a 20° upward gaze before and 3 months after surgery. RESULTS Preoperative IOP in upward gaze (18.7 mm Hg) was higher than in primary gaze (15.7 mm Hg, p < 0.001). Postoperative IOP reduction in upward gaze (3.8 mm Hg) was greater than in primary gaze (1.7 mm Hg, p < 0.001). Although the overall postoperative IOP in upward gaze (14.9 mm Hg) remained higher than in primary gaze (14.0 mm Hg, p = 0.038), the gaze-related IOP demonstrated no significant difference in all subgroups (Group A, p = 0.091; Group B, p = 0.332). CONCLUSIONS IOP in upward gaze was higher prior to orbital decompression, but reduction was greater postoperatively and approximated the IOP in primary gaze.