Objective Adrenal lymphoma is a rare entity in clinical practice, especially when presenting as Addison’s disease. Hence, we summarized the clinical features and outcomes of this rare disease in order to raise awareness in clinicians. Methods Clinical data of 5 cases of adrenal lymphoma admitted to our hospital from 1995 to 2014 were retrospectively analyzed. All of them were firstly diagnosed as Addison’s disease and then identified as adrenal lymphoma according to the results of pathology. Their signs, symptoms, tumor size, pathological types and results of laboratory examinations were analyzed, considering literatures review. Results The 5 patients were at an age of (66.4±6.6) years, with a male-to-female ratio of 4∶1. All of them manifested as typical signs and symptoms of Addison’s disease, such as systemic pigmentation, body mass loss, general fatigue and anorexia. They were diagnosed as primary adrenal non-Hodgkin’s lymphoma, with histological type of B-cell origin. Four of them were diagnosed with primary adrenal diffuse large B-cell lymphoma. R-CHOP chemotherapy was administered to all of them, but 2 died within 1 year, 1 died in 3 years, and only 2 survived till now. Conclusion Adrenal lymphoma presenting as Addison’s disease is more common in older males, and usually presents with bilateral adrenal glands. Ultrasound- or CT-guided needle biopsy of the adrenal tumor is necessary to make a definitive histopathological diagnosis. The main histological type is primary adrenal diffuse large B-cell lymphoma, and the prognosis is poor.