Many patients with cutaneous T-cell lymphoma (CTCL) experience severe pruritus. This study evaluated serum levels of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) in patients with CTCL. Although serum NGF and BDNF levels in patients with CTCL were not significantly higher than in healthy controls, serum NGF levels in patients with Sézary syndrome were higher than in those with mycosis fungoides and in healthy controls. Enhanced NGF expression by keratinocytes and increased dermal nerve fibres were detected in lesional skin of subjects with Sézary syndrome. Correlations between pruritus in CTCL and serum levels of NGF, BDNF, chemokine (C-C motif) ligand 1 (CCL1), CCL17, CCL26, CCL27, lactate dehydrogenase (LDH), IgE, and soluble interleukin-2 receptor were analysed. Serum CCL1, CCL26, LDH, and IgE levels correlated with pruritus in patients with CTCL. NGF may be associated with increased dermal nerve fibres and pruritus in Sézary syndrome, and CCL1, CCL26, and IgE may be associated with pruritus in CTCL.