Purpose. To evaluate intraocular pressure (IOP) after intravitreal instillation and eventual removal of silicone oil. Methods. The study included 198 patients who underwent pars plana vitrectomy with silicone oil endotamponade (5000 centistoke viscosity), in whom silicone oil was removed, and in whom follow-up after oil removal was at least 3 months. Results. After silicone oil instillation, IOP increased (P<0.001) from 12.9±4.4 mm Hg preoperatively to 16.1±5.5 mm Hg postoperatively. IOP was statistically (P>0.20) independent of the duration of silicone oil tamponade. Twenty percent of the 198 patients had at least one postoperative IOP measurement higher than 21 mm Hg. Main reasons for IOP elevation were closed inferior iridectomy, iris neovascularisation, secondary silicomakrophagocytic open-angle glaucoma, and preoperative history of glaucoma. Glaucomatous optic nerve damage was detected in 14 (14/198=7.1%) eyes including 8 eyes with preoperative antiglaucomatous treatment. Silicone oil emulsification occurring in 40 (40/198=20.2%) patients did not statistically influence IOP after oil removal. Ocular hypotony occurred in 10 (10/198=5.1%) patients after oil release leading to intraocular hemorrhages and loss of vision in three patients. Conclusion. Clinically significant elevation of intraocular pressure after pars plana vitrectomy with silicone oil endotamponade occurs relatively rarely, can usually be well controlled by topical antiglaucomatous medication, and is reversible in most of the patients after oil removal. In patients with elevated IOP and silicone oil endotamponade, oil removal may be preferred to invasive antiglaucomatous surgery to reduce IOP.