Primary acquired nasolacrimal duct obstruction (PANDO), which mainly occurs in the middle-aged and elderly women, is the most common type of obstructive diseases of the lacrimal duct, and it is also a common and frequently-occurring disease in ophthalmology. It constantly occurs secondary to various symptoms and signs of acute or chronic dacryocystitis, which seriously affects the daily work and life of patients. This article summarizes the research progress on the possible pathogenesis of PANDO in recent years, the urgent problems to be solved
and the hot research directions in the future, aiming to further deepen the understanding of the occurrence and development of lacrimal obstructive diseases.