We report a case of hemorrhagic detachment of Descemet's membrane after viscocanalostomy. A 60-year-old man with pseudoexfoliative glaucoma had an uneventful viscocanalostomy in the right eye. On the first postoperative day, a 5.0 mm x 5.0 mm Descemet's membrane detachment was present in the superior nasal quadrant. The space between Descemet's membrane and the stroma was filled with a hemorrhage. The hemorrhage resorbed by 6 months postoperatively, and Descemet's membrane completely reattached without surgical manipulation. The final visual acuity dropped from 20/40 to 20/100, final intraocular pressure was 20 mm Hg with 1 medication, and a paracentral fibrinoid scar persisted 18 months after surgery. Hemorrhagic detachment of Descemet's membrane can cause visual acuity deterioration and should be recognized as a rare complication of viscocanalostomy.