Purpose To evaluate the effect of 1 mg intracameral triamcinolone acetonide (TA) on postoperative intraocular pressure (IOP) after routine cataract surgery. Patients and methods This prospective, randomized, placebo-controlled study comprised 120 eyes of 120 patients with uncomplicated cataract surgery. The patients were randomized into two groups. Eyes in group 1 (60 eyes) received an injection of 1 mg TA into the anterior chamber at the end of the surgery, but eyes in group 2 (60 eyes) did not. The biomicroscopic evaluation, visual acuity (VA), and IOP measurements were done at baseline (preoperatively) and 6, 20-24 h, 1 week, and permonthly until 6 months postoperatively.Results Mean IOP at 6 and 20-24 h postoperatively were significantly higher than baseline measurements in both groups (Po0.001). Also, the mean IOP values at postoperative 6 and 20-24 h were slightly higher in group 1 than in group 2 (P40.05 for both). The mean IOPs at week 1 and 1-6 months after surgery were not significantly different from baseline values in both groups (P40.05 for both time periods). At 6 and 20-24 h postoperatively, the number of eyes with an IOP increase 45 and 10 mm Hg with respect to baseline were not statistically different between the two groups (P40.05). There were no statistically significant differences in mean VA and the amount of anterior chamber cells and flare between the two groups at any postoperative visit (P40.05).Conclusion Intracameral injection of 1 mg TA after uncomplicated phacoemulsification surgery had no significant effects on postoperative IOP.