Since Rosenwasser1reported the tumor of glomus jugulare in 1945, a number of cases have been reported; however, only a few cases showed evidence of catecholamine secretion.2-5Glomus jugulare tumor has been considered to originate embryologically in the neural crest and has been classified as a nonchromaffin paraganglioma because of the lack of chromaffinity. Previously only pheochromocytoma, among various neurogenic tumors, had been considered to secrete catecholamine, but since Mason et al6in 1957 reported a case of adrenaline-secreting neuroblastoma, a close relationship of neurogenic tumors to abnormal catecholamine secretion7has been recognized. We report a noradrenaline-secreting tumor of the glomus jugulare with catecholamine granules shown electron microscopically. Continuous recording of blood pressure showed a peculiar cyclic change of the pressure. METHODS Catecholamine was measured by a modification of the trihydroxyindole fluorimetric method of von Euler and Floding.8Levels of urinary total metanephrine (TMN)