Pituitary abscess is a rare intrasellar infectious disease. It is usually treated with a combination of surgical drainage and intravenous antibiotics. We describe the case of a 38-year-old man with headache, fever, left earache, subsequent diabetes insipidus, and anterior pituitary insufficiency due to pituitary abscess, which was confirmed on the basis of clinical symptoms, laboratory examination results, and magnetic resonance imaging features. He was treated nonsurgically with intravenous antibiotics, with complete resolution of the pituitary abscess and recovery of pituitary function. Nonsurgical treatment may be an option for pituitary abscess.