After bone marrow transplantation various ocular diseases have been described. Ocular involvement is very common in patients with chronic Graft-versus-Host Disease (GvHD). These patients show clinical and histological evidence of a dry-eye condition in 60-100 per cent. A severe complication is the development of a corneal ulcer with possible corneal perforation. Two patients with a severe dry-eye condition and development of corneal stroma ulceration are described. The corneal ulcers healed after treatment with collagen-shield.In a 13-year-old boy an allogeneic bone marrow transplantation was performed in April 1989 because of Fanconi's anemia. In November 1989 a severe dry-eye condition occurred due to GvHD with skin, liver, and gastrointestinal tract manifestation. In April 1991 he presented with corneal stroma ulceration of the right eye. In a 24-year-old patient an allogeneic bone marrow transplantation was performed because of chronic myeloid leukemia in August 1989. In December 1989 he developed dry-eye condition due to GvHD with skin, mucosa and liver involvement. In December 1991 a corneal ulcer of the left eye occurred.Repeated conjunctival and corneal smears were negative. Local antibiotic and antiviral treatment showed no effect. Corneal ulcers deteriorated progressively with corneal thinning. Both patients were therefore treated with daily collagen-shields and hourly polyvinyl-pyrrolidon eye-drops resulting in healing of the corneal ulcer within 3 and 2 weeks respectively.Treatment of corneal stromal ulceration in dry eye condition caused by chronic GvHD is difficult. In noninfectious ulcers daily application of collagen-shields and hourly artificial tears may prevent severe ocular complications like corneal perforation.