BackgroundMyelolipoma is a benign neoplasm of the adrenal cortex, composed of fat and hematopoietic cells. Although myelolipoma is benign, differentiation from adrenocortical cancer may be difficult. The presence of adrenal and extra-adrenal myelolipomas simultaneously is sporadic, making it a challenging case, especially when the preoperative diagnosis is ambiguous.Case presentationA 65-year-old man was referred to our clinic due to a mass in the adrenal fossa. In the abdominopelvic computed tomography (CT), a well-circumscribed fat-containing 78 × 61 × 65 mm bi-lobulated mass was reported in the left adrenal fossa. The first differential diagnosis was myelolipoma. The patient was then referred to our clinic for a mass excision. He was asymptomatic and was scheduled to undergo laparoscopic-assisted adrenalectomy. After adrenalectomy and mass dissection, surprisingly, another mass was detected in the retroperitoneal area. The second mass was also dissected. The final diagnosis was myelolipoma for both masses. The patient has been symptom-free for nine months after the operation.ConclusionSimultaneous adrenal and extra-adrenal myelolipoma should be considered as one of the differential diagnoses. However, because this situation is extremely rare, the probability of malignancy should be highly regarded, and we suggest an obsessive approach when approaching this condition. It is essential to manage these cases on a case-by-case basis and tailor the management concerning intraoperative biopsy, the intraoperative appearance of tumors, and the location of extra-adrenal masses.