Background: The primary aldosteronism (PA) is one of the secondary hypertension causes. The classic presenting signs are hypertension (HTN) and hypokalemia. Objectives: The study aimed to differentiate between aldosterone-producing adenoma (APA) which is surgically curable and the bilateral adrenal hyperplasia (BAH) which is medically treatable. Material and methods: A case study of a 35 years old Saudi male patient referred from primary health care center with uncontrolled HTN. Results: In presence of hypertension, hypokalemia and metabolic alkalosis, the primary aldosteronism should be suspected. Patients with PA, a challenging task is to differentiate between aldosterone-producing adenoma (APA) which is surgically curable and the bilateral adrenal hyperplasia (BAH) which is medically treatable. The differentiation usually require adrenal venous sampling however it is costly, invasive, with high risk and not available in most of centers. There is relation between elevated parathyroid hormone and APA in patients with biochemically confirmed primary aldosteronism. Conclusion: In patients with confirmed PA, routine assessment of serum parathyroid hormone may be helpful to identify those who are more likely to have APA, which is treated surgically before the adrenal venous sampling.