Primary lymphoma of bone is a rare form of non-Hodgkin lymphoma which involves a single bone and has a relatively good prognosis following radiation therapy. We observed 17 histologically verified cases and found 97 cases in the literature. This rare tumour may occur at any time in adults and usually affects the metaphyses of long bones. It produces osteolytic changes and usually only mild periosteal reactions. Radiologically as well as histologically, differentiation from other highly malignant bone tumours is extremely difficult and sometimes impossible. A correct diagnosis can only be made from an accurate knowledge of the radiological appearances, localisation of the tumour and age of the patient.