Left adrenal nodules can be caused by a number of different etiologies. Primary adrenal nodules include aldosterone tumors, non-functioning adrenocortical adenomas, pheochromocytomas, and adrenocortical carcinomas. Non-adrenal primary nodules include metastatic cancer. It is recommended to make a definite diagnosis under the guidance of a doctor. Functional adenomas have endocrine function and can secrete hormones such as cortisol or aldosterone, causing endocrine disruption. If too much aldosterone is secreted, it can cause symptoms such as high blood pressure and low blood potassium. Most functional adenomas require surgery to remove the adenoma, along with treatment. Non-functional adenomas can be treated without special treatment if the occupancy is small and the patient is asymptomatic, but regular review is needed. It is recommended that patients with left adrenal nodule should seek timely medical treatment to clarify the type of disease under the guidance of the doctor and treat the symptoms to avoid delaying the condition.