BACKGROUND Patients with end-stage renal disease undergoing long-term maintenance hemodialysis are more likely than the general population to exhibit primary hypothyroidism. Only a few cases of isolated adrenocorticotropic hormone deficiency (IAD) among hemodialysis patients have been reported. We herein report an unusual case of a patient undergoing long-term hemodialysis who exhibited both IAD and primary hypothyroidism. CASE REPORT A 82-year-old male with end-stage renal disease secondary to immunoglobulin A nephropathy, undergoing hemodialysis for 20 years, was found to have primary hypothyroidism without obvious symptoms and consequently began thyroid hormone replacement therapy with oral levothyroxine. At 84 years of age, he developed anorexia, fatigue, and lethargy. A systemic workup using computed tomography and gastrointestinal endoscopy detected no abnormalities. He did not exhibit electrolyte imbalances, such as hyponatremia or hyperkalemia, and had normal morning blood levels of cortisol and adrenocorticotropic hormone. However, he exhibited hypoglycemic coma 4 months later. Detailed endocrinological examinations using dynamic function tests indicated IAD. After commencement of corticosteroid replacement therapy, his symptoms resolved without complications. CONCLUSIONS To our knowledge, this is the first report of a hemodialysis patient with both IAD and primary hypothyroidism. This case highlights the importance of regular assessments of thyroid function for primary hypothyroidism in hemodialysis patients, even when they are asymptomatic. Furthermore, timely dynamic endocrine testing of hypothalamic-pituitary-adrenal function is needed to diagnose possible IAD in hemodialysis patients with symptoms suggestive of adrenal insufficiency, even in the absence of abnormal laboratory findings such as electrolyte imbalances or low morning blood levels of cortisol or adrenocorticotropic hormone.