The light and ultrastructural analyses of an extradural intraspinal angiolipoma causing symptoms of spinal cord compression, are reported. The tumour showed morphological evidence of an endocrine-like secretory activity of fat cells, with an apparent mechanism of secretory function that has not previously been described for angiolipomas. The secretory granules, containing a lipid-like material, were covered with a continuous basement membrane originating from the basement membrane of the adipocyte.