Tumors of the lacrimal drainage system, especially the lacrimal sac, are rare. Despite their rarity, physicians should be aware of the clinical features of lacrimal sac tumors, as many are life-threatening and early diagnosis and appropriate treatment can save lives. These tumors often masquerade as a chronic inflammatory process. Due to the rarity of lacrimal sac tumors, large clinical studies with statistically meaningful data are unavailable, and we learn about the biological behavior, management, and prognosis of these tumors only from case series and case reports. Lacrimal sac tumors are usually diagnosed in adults, while more than half of them are malignant. About three-quarters of these tumors are of epithelial origin. The main sign of these tumors is a mass in the lacrimal sac area. Although most of the tumors present with symptoms of lacrimal drainage obstructions, many of them are found inadvertently at the time of dacryocystorhinostomy (DCR). Therefore, it has been suggested by some authors that a lacrimal sac biopsy during a DCR should always be submitted for pathological evaluation. Other surgeons use criteria discussed in this chapter to obtain histopathology in specific cases. Imaging techniques, such as CT scan, MRI, ultrasound, and dcryocystography, may help in the diagnosis. Complete surgical removal by various techniques is the gold standard in treating lacrimal sac tumors, accompanied in malignant cases by radiation therapy, chemotherapy, and when needed, followed by reconstruction. Recurrence and mortality rate vary according to the type of the tumor and its extent.