During the period from Jan. 1 1989 to June 30 1992 at the Urological Clinic in Hradec Králové three women with cortical adenomas were treated, the tumour being the cause of primary hyperaldosteronism. The age of the patients was 25-40 years, in one woman the tumour was on the right side, in two on the left side. All patients complained of marked muscular weakness, fatigue, one woman developed cramps of the hands when working and another patient was repeatedly hospitalized at the neurological department on account of attacks of weakness. In one patient the interval from the onset of complaints to assessment of the diagnosis was 23 years. All patients had complete examinations at specialized departments before operation, in all the diagnosis was established by biochemical examinations and CT. In all instances minor tumours--diameter 2-3 cm--were involved which were easily removed by surgery. The postoperative course in all patients was without complications.