Anaplastic, CD30⁺, large-cell lymphoma (ALCL) is a subtype of non-Hodgkin’s lymphoma that accounts for 2% to 8% of all lymphomas. Its most common form is a classical systemic type, which involves multiple nodal and extranodal sites, including the skin. Malignant lymphoproliferative disorders, especially Hodgkin’s disease, are known rarely to be associated with acquired ichthyosis, whereas only 1 case of ALCL has been reported to be associated with acquired ichthyosis. We describe a 74-year-old Japanese man with ALCL, involving lymph nodes and the skin, who exhibited acquired ichthyosis. The clinical and histopathologic findings were recorded, and immunophenotyping, T-cell receptor (TCR), and immunoglobulin gene rearrangement were determined. Clinically, right axillary and bilateral inguinal lymph nodes were palpable. The cutaneous eruptions were multiple pinkish and yellow colored, up to thumb-sized nodules, some of which were ulcerated. Histologically, the right axillary lymph node showed proliferation of anaplastic large cells in the paracortical and sinusoidal areas. Both the lymph node and skin showed pleomorphic proliferation of lymphoid cells with a mixture of mononuclear cells having oval, embryo-shaped, reniform, and lobulated nuclei, binucleated Reed-Sternberg–like cells, and multinucleated cells, with giant anaplastic and wreath-shaped nuclei. Immunophenotyping of the neoplastic cells revealed that they were positive for CD30 (Ber-H2), CD15 (Leu-M1), CD45 (LCA), and CD45RO (UCHL-1). Southern blot analysis demonstrated clonal rearrangement of the TCR β region. In contrast, no novel bands were detected with the immunoglobulin heavy chain JH probe. Several months after the detection of the axillary nodes, an ichthyosiform, scaly eruption developed over almost the entire body of the patient. Histologically, it showed orthokeratotic, slight hyperkeratosis of the epidermis without a granular layer or with only a single layer of cells in the granular layer. Several kinds of lymphoproliferative diseases are associated with acquired ichthyosis, including Hodgkin’s disease, multiple myeloma, and lymphomatoid papulosis. This is the second case report of acquired ichthyosis associated with ALCL. Although a common pathomechanism is suspected of underlying the development of acquired ichthyosis in these diseases, it is still unexplained. (J Am Acad Dermatol 2000;42:914-20.)