Purpose The purpose of this study was to determine the incidence of and risk factors for intraocular pressure (IOP) elevation within 24 h following vitrectomy for rhegmatogenous retinal detachment (RD). Methods We assessed 34 eyes of 34 consecutive patients with RD undergoing vitrectomy and 12 eyes of 12 patients with macular hole as controls. IOP was measured using Tonopen XL before surgery, at the end of surgery, and at 5 h and 1 day postoperatively. IOP at the end of surgery was adjusted to 15.0 ± 2.0 mmHg. Results IOP elevation was found in five RD eyes at 5 h and in 13 1 day postoperatively. IOP in patients with RD at both 5 h and 1 day postoperatively was significantly higher than that of controls. Circumferential dimension of retinal tears and disease duration were significantly associated with IOP elevation at both 5 h and 1 day postoperatively. Conclusions IOP elevation in the early postoperative period following vitrectomy for RD is common. The risk factors for IOP elevation include the extent of retinal tears and duration of detachment. Prophylactic treatment may be useful in eyes with higher risks of IOP elevation.