The radiological findings in 39 patients with a manifestation of eosinophilic granuloma (e.g.) other than skull and spine were evaluated. The localisation was found in the femur (26%), clavicula (20%) and ribs (20%). The lesions were located in 81% in the diaphysis and in 9.5% either in the epi-metaphysis or epi-metadiaphysis. Associated periosteal reactions were observed in 38% of the patients, and were solid in 25%, lamellar in 10%, and in 3% complex. The majority of the tumours were classified as Lodwick IB lesions (41%). Lodwick IC lesions were seen in 13%, Lodwick II lesions in 25.5% and Lodwick III lesions in 20.5% of the patients. In patients below the age of 20 years the eosinophilic granuloma is characterised by a Lodwick IB lesion without or with a solid periosteal reaction, which allows differentiation from Ewing's sarcoma or osteomyelitis. Contrariwise, in patients above 20 years of age the e.g. appears with a higher Lodwick grade. Hence, differentiation, X-ray morphology, between e.g., metastasis, lymphoma, and multiple myeloma does not seem possible.