Purpose: To report a case of acute angle closure glaucoma from spontaneous massive hemorrhagic retinal detachment from hypertension and diabetes mellitus. Methods: A 52-year-old woman with controlled systemic hypertension and newly diagnosed diabetes mellitus presented with sudden onset painful loss of vision of the right eye. Examination of the right eye showed no light perception, an intraocular pressure of 60 with shallow anterior chamber, microystic corneal edema, closed angles on gonioscopy, and massive subretinal hemorrhage on indirect ophthalmoscopy. The left eye was essentially normal except for arterio-venous crossing changes. Ocular ultrasound revealed massive subretinal hemorrhage with possible intraocular mass. Enucleation of the painful blind eye was done for histologic diagnosis. Results: The ocular pathology revealed complete angle closure with total retinal detachment from massive subretinal hemorrhage with no mass or tumor seen. Metastatic work-up included liver enzymes, mammography, transvaginal ultrasound, chest radiography, and cranial and abdominal computerized tomography which were all normal. Conclusion: Hypertension and diabetes mellitus may cause spontaneous massive subretinal hemorrhagic retinal detachment resulting in secondary angle closure glaucoma. Enucleation is a therapeutic option if a suspicion of an intraocular tumor is present.