Post-transplant lymphoproliferative syndrome (PFS) confined to the central nervous system (CNS) is an extremely rare and poor prognosis. The treatment has a significant impact on survival. This standard is not clearly given the low incidence of this condition and therefore there is little literature. Radiotherapy is an alternative treatment in these patients with involvement in the CNS. A review of the main characteristics of this pathology was conducted and a case of a patient of 13 years old with CNC SLPT confined to the only site of involvement, treated with radiotherapy getting a good response, adequate tolerance to treatment.