Two cases of fibroelastoma of the back are reported. It is pointed out that probability diagnosis in mainly entrusted to the objective examination and to the typical site of tumefaction, backed by echotomography, xeroradiography and computerised tomography and demonstrated by histological examination of the operative piece. Differential diagnosis has to be established versus fibrosarcoma, liposarcoma, desmoid tumour and malignant tumour of the synovia. The need for surgical removal is reiterated.