To study dermatological manifestation of T-lymphoblastic lymphoma and to help clinicians in the diagnosis, we report here the case of a 75-year-old patient who presented with violaceous nodules acquired during the last 4 wk and affecting the scalp and right arm. The diagnosis of systemic lymphoma was suggested upon the appearance of cutaneous tumors, palpable lymph nodes and general symptoms including asthenia and weight-loss. The pathology features: positive immunostaining for CD3 and terminal deoxynucleotidyl transferase (TdT) and staging, led us to the final diagnosis of T-lymphoblastic lymphoma (T-LBL) with cutaneous involvement. He received a CHOP regimen as first-line treatment. Unfortunately, the patient relapsed and died 8 mo after the treatment initiation. T-LBL may be diagnosed by skin lesions. Additional immunostaining including TdT and experienced histopathologists are needed to correctly classify this aggressive disease and discuss the correct management including bone-marrow transplantation where appropriate.