Blood pressure (BP) level is similar in patients with 3 subtypes of primary aldosteronism (PA), even though aldosterone levels may vary. Glucocorticoids and adrenomedullary hormones may be influenced and may contribute to hypertension in PA. The authors' objective was to investigate the influence of PA on adrenal gland secretion and the roles of these hormones in hypertension. Patients diagnosed with PA (229 cases) were enrolled and classified into 3 subgroups: aldosterone-producing adenoma (APA), unilateral nodular adrenal hyperplasia (UNAH), and idiopathic hyperaldosteronism (IHA). Patients with essential hypertension served as the control group (100 cases). Concentration of the above hormones was measured and compared between groups. Level of plasma adrenocorticotrophic hormone (ACTH) in patients with APA was significantly lower than that in patients with IHA (P<.001) and UNAH (P<0.5). The 24-hour urinary free cortisol and adrenomedullary hormone levels were highest in patients with IHA, lower in patients with APA, and lowest in patients with UNAH. Systolic BP level was positively correlated with 8 am plasma cortisol level (r=0.142, P=.039) and plasma ACTH level (r=0.383, P=.016). Cortisol and adrenomedullary hormones were different between PA subtypes and they might involve regulation of BP in those patients.