The authors report two cases of intradural metastasis: a man with bronchopulmonary cancer suffering from left L5 sciatic pain and a woman with breast cancer whose examination shows motor weakness of both legs. CT was negative in the first case. Gadolinium injection on T1 sequence shows in the first case small nodular lesions along the roots of cauda equina and in the second case linear enhancements around the spine, at different levels. These aspects are the most frequently reported. MRI is an innocuous and the most sensitive technic for such lesions. An early diagnosis improves the functional prognosis. Despite of radiotherapy and chemotherapy, vital prognosis remains bad because of widespread of the intradural lesions and their frequent association with cerebral metastasis.