Deep or intramuscular juvenile xanthogranuloma (JXG) is very rare. There are, however, some clinical and histological similarities between the case we present and the few cases that have been published in the literature. Although most of them will need histologic confirmation to establish the final diagnosis, surgeons who are operating tumors of infancy should consider it in the differential diagnosis of well circumscribed, rapidly growing dorsal masses in children under 3 years of age. Macroscopic appearance upon excision can help to support the diagnosis. Knowledge of this variant of JXG may avoid aggressive diagnostic or therapeutic procedures.