Pheochromocytomas are most commonly found in the kidney and peri-adrenal glands, both sides of the abdominal aorta, the bladder wall at the end of the ureter, the thorax, the myocardium, the carotid body and the skull. In addition to adrenaline and norepinephrine, pheochromocytomas can also synthesize other hormones and can be complicated by other endocrine system tumors, causing a variety of endocrine dysfunctions. Approximately 10% of patients with pheochromocytoma have a family history of autosomal dominant inheritance, and the incidence of multiple and extra-adrenal tumors is higher than that of those without a family history. The history of understanding pheochromocytoma is relatively short, with the first successful resection of pheochromocytoma by Roux and Mayo in 1926. The surgical mortality rate for pheochromocytomas remained as high as 26%, until the early 1950s. It was only with the subsequent application of adrenergic receptor blockers and attention to timely blood volume replacement that the mortality rate decreased significantly. This indicates that our understanding of the intricate and unpredictable nature of pheochromocytoma symptoms is still very incomplete, resulting in some patients not receiving timely and correct diagnosis and delaying treatment. In the past, pheochromocytoma was considered a rare disease, and with the emphasis on this disease and the improvement of detection techniques, many cases were able to be screened out from hypertension. In the last 30 years, the number of cases of pheochromocytoma in China has increased dramatically, with large groups of tens or even hundreds of cases reported in Beijing, Shanghai, Guangzhou, Wuhan, Nanjing, and Changsha, and the treatment techniques have also improved significantly. After the 1960s, due to the adoption of various advanced diagnostic techniques, extra-adrenal tumors, familial pheochromocytomas and multiple tumors of endocrine glands, which were not easily diagnosed in the past, have been discovered one after another, and the probability of extra-adrenal tumors, bilateral tumors, multiple tumors and malignant tumors has far exceeded 10%. In recent years, domestic and international statistics show that only 60%-80% of pheochromocytomas in the adrenal glands are solitary. The incidence of pheochromocytoma in men and women is approximately equal. The age of onset is highest in the 20-40 years group. The incidence of pheochromocytoma in pediatric patients is slightly higher in males, with familial prevalence and bilateral multiple tumors accounting for 39% of cases. Pheochromocytomas can be found in all parts of the body above the pelvis. The etiology and clinical significance of pheochromocytomas are more complex if they grow in certain specific areas.