The occurrence of lymphomatoid papulosis in patients with cutaneous lymphoma, particularly mycosis fungoides, has been described in medical literature. A 68-year-old woman affected by mycosis fungoides in the plaque stage noticed that multiple papulonodular lesions of lymphomatoid papulosis developed suddenly after a few sessions of PUVA therapy. The PUVA induction of lymphomatoid papulosis was confirmed by the appearance of new lesions after a second cycle of PUVA exposure on a limited area of the body. Complete regression of all PUVA-induced lymphomatoid papulosis lesions was achieved within a few weeks with oral prednisone and topical steroids. During the entire treatment the patches and plaques of mycosis fungoides persisted unchanged.