A case of cutaneous T cell lymphoma associated with mild eosinophilia and rise of IgE levels is reported. A population of CD3-CD4+ cells was observed in the peripheral blood. After activation, these purified CD3-CD4+ cells showed a Th2 pattern of cytokine production, secreting higher levels of IL-5 and IL-4 and lower levels of IFN-gamma compared to the patient's and controls' CD3+CD4+ cells. Moreover, high levels of IL-5 and soluble CD30, a marker of Th2 cell activation, were detected in the patient's serum.