Chronic graft-vs-host disease (GVHD) is an immunologic disorder frequently occurring as a late sequelae of allogeneic bone marrow transplantation and characterized in the skin with lichenoid or sclerodermoid lesions. Systemic immunosuppressive agents such as corticosteroids or cyclosporine are usually required to control the disease. Therapy with psoralen and UVA (PUVA) has recently been shown to be effective for skin and oral mucosa in a few cases of GVHD. We present our experience with PUVA in six patients, five with lichenoid and one with sclerodermoid GVHD. None of these patients had significant systemic involvement. All five patients with lichenoid GVHD showed clinical improvement after PUVA therapy. Three of these patients had complete clearance of skin lesions. Clinical clearance of the disease was accompanied by microscopic clearance. The patient with sclerodermoid GVHD did not respond to therapy. No significant complications or exacerbation of systemic disease occurred. We confirm that PUVA is an effective and safe therapy for the cutaneous manifestations of lichenoid chronic GVHD. We postulate that PUVA therapy clears chronic lichenoid GVHD by selective cytotoxicity for the activated lymphoid cells in the inflammatory infiltrate.