Lacrimal sac tumors are rare with a clinical presentation that typically includes obstruction of the lacrimal drainage system and epiphora as the most frequent symptom. Cribriform adenoid cystic carcinoma (ACC) is the most common malignant epithelial tumor of the lacrimal gland and minor salivary glands; however, its occurrence in the lacrimal drainage apparatus is extremely rare. Given the rarity of ACC, definitive diagnosis is almost invariably late conferring a poor prognosis. Herein we report the case of a 41-year-old woman with primary ACC of the lacrimal sac and describe the ophthalmological examination, diagnosis, and multidisciplinary treatment of this rare type of tumor. Keywords