Hypopituitarism is characterized by an underactive pituitary gland and may result in growth hormone deficiency, hypothyroidism, testosterone deficiency, and/or adrenal insufficiency. Traumatic brain injury (TBI) exposure is a known risk factor for hypopituitarism. However, patients with hypopituitarism secondary to TBI exposure may go undiagnosed because the signs and symptoms of hypopituitarism can be subtle. This case report describes a 40-year-old male US military veteran who endorsed fatigue, sexual dysfunction, and weight gain several years after experiencing multiple mild TBIs during his military service. He ultimately underwent a full neuroendocrine workup that revealed low testosterone in addition to previously diagnosed hypothyroidism with a resolution of symptoms after starting testosterone therapy.