The adrenals are a common site of metastases for lung cancers; adrenal insufficiency, however, as a presenting feature of lung cancer, is extremely rare. We report a case of primary adrenal insufficiency secondary to metastases from adenocarcinoma of the lung. Our patient presented with hypotension, abdominal pain, and weight loss. CT scans showed a right upper lobe mass and bilateral adrenal masses. The frequent occurrence of constitutional symptoms, metabolic derangements, and cardiovascular compromise in patients with advanced cancer may lead to an underestimation of the true incidence of adrenal insufficiency in this population.