Objective To research the incidence and etiological factors of intraocular pressure(IOP)elevation in patients in early and late postop?erative stages after vitrectomy. Methods The clinical data of 235 cases(306 eyes)who underwent vitrectomy in our hospital were respectively ana?lyzed. IOP was measured before operation,in the early postoperative stage(within 2 weeks)and in the late postoperative stage(6 months after opera?tion or longer)by non?contact tonometer. Risk factors related with ocular hypertension happened in the early and late postoperative stages were statis?tically analyzed. Results The mean average IOP before operation was 15.3 ± 4.1 mmHg for the 306 eyes. Within the follow?up period of 6?20 months(mean,14.3 months),ocular hypertension occurred in 42 eyes[incidence,13.7%;mean,31.9 ± 6.0 mmHg]in the early postoperative stage and in 12 eyes[incidence,3.9%;mean,32.1 ± 5.7 mmHg]in the late postoperative stage. Logistic regression analysis revealed that lensecto?my,scleral buckling,cyclophotocoagulation,inert gas filling,silicone oil tamponade and diabetic retinopathy were the independent risk factors of oc?ular hypertension in early postoperative stage after vitrectomy,while lensectomy,scleral buckling,pan retinal photocoagulation,silicone oil tampon?ade,diabetic retinopathy and carotid artery stenosis were the independent risk factors of ocular hypertension in late postoperative stage after vitrecto?my. In addition,cyclophotocoagulation was a protective factor of IOP in the late postoperative stage. Conclusion The risk factors of ocular hyperten?sion after vitrectomy include the intraocular gapfiller,the mode of combined operation,disease type and carotid artery stenosis. IOP elevation that happens in the late postoperative stage is more harmful. Ocular hypertension in the late postoperative stage is not associated with that in the early stage.