An 81-year-old man with unilateral nasolacrimal duct obstruction underwent routine endonasal dacryocystorhinostomy and 2 days postoperatively developed a severe headache and rigors. Subsequent CT and MRI imaging demonstrated a defect in the floor of the right anterior cranial fossa, which possibly was damaged during the operation, and meningoencephalitis of the adjacent frontal lobe gyrus. Following intravenous antibiotic treatment, the patient made a full recovery with no ongoing sequelae, and his epiphora completely resolved. To the authors' knowledge, this is the first report of meningoencephalitis following endonasal dacryocystorhinostomy. This complication should be considered in any patient with a febrile septic presentation or headache following endonasal dacryocystorhinostomy.