Pheochromocytoma is a tumor originating from chromophobic tissue of neuroectodermal layer and mainly secretes catecholamines. Paragangliomas are classified into parasympathetic paragangliomas (including chemoreceptor tumors and carotid body tumors) and sympathetic paragangliomas (including retroperitoneal, pelvic and mediastinal paragangliomas) according to whether the tumor is from sympathetic or parasympathetic nerves. Some patients may suffer from severe cardiac, cerebral and renal damage due to long-term hypertension or sudden onset of severe hypertension leading to life-threatening crisis, but if timely and early diagnosis and treatment are obtained, it is a curable secondary hypertensive disease. Etiology: Pheochromocytoma is a tumor that originates from adrenal chromaffin cells and overproduces catecholamines, causing persistent or paroxysmal hypertension and multiple organ dysfunctions and metabolic disorders. Pheochromocytoma can originate from the adrenal medulla, sympathetic ganglion or other sites of chromophobic tissue. More than 90% of pheochromocytomas are benign tumors. 80-90% of chromophobe tumors occur in chromophores of the adrenal medulla, and 90% of them are unilateral single lesions. Pheochromocytomas originating from outside the adrenal glands account for about 10%, and malignant pheochromocytomas account for about 5-10%. Diagnosis: Pheochromocytoma should be considered with the following clinical manifestations: 1. Hypertension: paroxysmal, persistent, or persistent hypertension with paroxysmal exacerbation; pressure on the abdomen, activity, emotional changes or urination and defecation can trigger hypertensive episodes; general antihypertensive drug therapy is often ineffective. 2, hypertension attacks with headache, palpitations, excessive sweating triad performance. 3.Patients with hypertension have postural hypotension at the same time. 4, hypertensive patients with abnormalities in glucose and lipid metabolism, abdominal masses. 5.Patients with hypertension accompanied by cardiovascular, digestive, urinary, respiratory, neurological and other related signs, but hypertension that cannot be explained by diseases of that system should undergo clinical evaluation and confirmatory examination of pheochromocytoma. Pheochromocytoma localization diagnosis, CT and MRI can detect tumors in the adrenal gland or abdominal para-aortic sympathetic ganglion, and MIBG scan has -certain advantages for the localization of extra-adrenal, recurrent or metastatic tumors. Functional diagnosis mainly relies on biochemical detection of catecholamine content in body fluids, which includes epinephrine, norepinephrine and dopamine and their metabolites; m-adrenaline analogues are metabolites of catecholamines, which have the advantages of longer half-life, less susceptible to fluctuations and less affected by drugs, and have better diagnostic value than catecholamine assay. Treatment: Most pheochromocytomas are benign, and surgical resection is the most effective treatment. 131I-MIBG therapy is the most valuable treatment other than surgical resection of tumors, and is mainly used for the treatment of malignant and surgically unresectable pheochromocytomas. The drug of choice is α-adrenergic receptor blockers and, if necessary, β-adrenergic receptor blockers.