A 35-year-old woman underwent excimer laser penetrating keratoplasty for macular corneal dystrophy in the right eye. Two months after surgery, a thin transparent membrane behind the clear corneal graft was noted. Anterior segment optical coherence tomography revealed duplication of the anterior chamber by this membrane, originating from the host cornea without direct contact to the donor tissue. Trypan-blue-assisted descemetorhexis was performed, and histopathology confirmed the diagnosis of retained Descemet's membrane. Four months later, the graft was clear with good visual acuity and no sign of retrocorneal membrane.