Gallium-67 is a non-specific tumor seeker and a good guide to the activity of a lymphoma. The appearance on gallium-67 imaging in mycosis fungoides has so far demonstrated either no tracer uptake or increased tracer uptake at the lesion. A 78-year-old woman presented with erythroderma of 20 years duration and a skin tumor in the left hip area, which became ulcerated. Gallium-67 imaging revealed increased uptake in the left hip lesion. A biopsy demonstrated mycosis fungoides. A case of mycosis fungoides with increased gallium-67 uptake in an ulcerating skin tumor lesion is reported.